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ATLAS  AND  TEXT-BOOK 

OF 

DENTISTRY 


INCLUDING 


DISEASES  OF  THE  MOUTH 

BY 

GUSTAV   PREISWERK,  M.  D.,  PH.  D. 

UNIVERSITY  OF  BASEL,  SWITZERLAND 


AUTHORIZED    TRANSLATION   FROM  THE  GERMAN 


EDITED  BY 

GEORGE  W.  WARREN,  A.  M.,  D.  D.  S. 

PROFESSOR  OF  PRINCIPLES  AND  PRACTICE  OF  OPERATIVE  DENTISTRY, 
PENNSYLVANIA  COLLEGE  OF  DENTAL  SURGERY 


With  t03  colored  figures  on  44  plates  and  1 52  text-illustrations 


PHILADELPHIA   AND    LONDON 

W.   B.   SAUNDERS   COMPANY 
1909 


Copyright,  1906,  by  W.    B.   Saunders  Company 


Reprinted  April,  igog 


PRINTED    IN    AMERICA 


PRESS    OF 

W.    B.    SAUNDERS    COMPANY 

PHILADELPHIA 


EDITOR'S  NOTE. 


An  American  edition  of  Preiswerk's  "  Text-Book  and 
Atlas  of  Dentistry,"  translated  from  the  German,  will  be 
Avelcomed  by  both  students  and  practitioners.  The  author 
is  one  of  the  chief  exponents  of  the  modern  trend  of 
dental  thought  in  Germany  ;  and,  while  we  may  not  entirely 
agree  with  all  of  his  views  as  here  expressed,  the  book 
will  be  much  appreciated  as  a  fair  presentation  of  dental 
practice  in  that  country. 

Our  thanks  are  due  the  author  for  the  large  number  of 
splendid  illustrations,  indicative  of  extended  clinical  expe- 
rience, much  labor,  and  great  care.  They  will  add  much 
to  the  student's  interest  in  the  subject. 

The  editor  has  had  much  interest  and  pleasure  in  pre- 
paring the  book  for  publication. 


PREFACE. 

The  publisher,  Mr.  J.  F.  Lebmann,  being,  as  I  well 
knew,  ever  ready  to  comply  with  any  reasonable  wishes 
on  the  part  of  his  authors,  it  was  with  enthusiasm  that  I 
undertook  to  write  an  illustrated  text-book  of  dentistry, 
and  my  expectations  in  this  respect  were  not  disappointed 
— on  the  contrary,  I  look  back  on  our  correspondence  relat- 
ing to  the  preparation  of  the  book  with  the  greatest  satis- 
faction. 

Mr.  Lehman u's  liberality  enabled  us  to  turn  out  an 
excellent  set  of  illustrations,  which  greatly  add  to  the 
beauty  of  the  book.  A  number  of  artists  contributed  to 
the  preparation  of  the  plates  and  figures.  Most  of  the 
colored  plates  were  painted  by  Mr.  Fink.  Mr.  Oser  con- 
tributed, in  addition  to  several  drawings  in  black  and 
white,  Plates  28  to  37,  while  Plates  7  and  9  arc  tbe  work 
of  Mr.  Biichli.  Tbe  drawings  for  Figures  4,  5,  6,  9,  and 
10  were  prepared  by  Mr.  Fiechter,  and  Figure  133  by 
Mr.  Albrecht  Meyer. 

The  efforts  of  all  these  gentlemen  were  as  honest  and 
untiring  as  their  results  are  successful. 

By  far  the  greater  number  of  the  specimens  from  which 
the  illustrations  were  copied  were  furnished  by  myself.  I 
received  much  valuable  assistance  in  this  ]:>art  of  the  worlc 
from  Professor  (Dr.)  Jos.  Arkovy,  who  })laced  at  my  dis- 
posal fifty-nine  watcM*  colors  painted  by  Dr.  Marikovszky. 
With  the  aid  of  some  clinical  specimensof  my  own  these  were 

7 


8  PREFACE. 

, reduced  to  a  smaller  scale  by  Mr.  Fink,  and  reproduced  in 
Plates  25  to  27  and  39  to  44.  I  am  also  indebted  to  Professor 
(Dr.)  Jul.  Kollmann  for  the  use  of  several  specimens  from 
the  anatomical  collection  in  this  city  (Plates  1,  2,  and  4 
and  Figure  82).  From  Professor  (Dr.)  Ed.  Kaufmann  I 
received  the  cyst  represented  in  Figure  54,  and  Professor 
(Dr.)  Friedrich  Miiller  kindly  supplied  me  with  a  case  of 
typhoid  ulcer  from  his  clinic  (Plate  13  a).  The  section  of 
au  alveolar  process  and  root  of  a  tooth  reproduced  in  Plate 
5,  Figure  l,was  obtained  from  the  collection  of  anatomical 
specimens  of  Dr.  Romer,  Docent  in  Strassburg  ;  while  the 
examples  of  hypoplasia  shown  in  Plates  19  and  20  were 
sent  to  me  by  Professor  (Dr.)  Billeter  in  Zurich.  The 
following  are  borrowed  from  text-books  :  Figures  40  to  42 
(R5se),  Figures  Q,  8  and  9  (Merkel),  and  Figure  97  (Miller). 

In  the  correction  of  proof  I  was  assisted  by  my  colleague 
Dr.  Paul  Witzig,  Dr.  Gustav  Leimgruber,  and  my  brother 
Paul  Preiswerk,  to  all  of  whom  I  wish  to  express  my 
Avarmest  thanks  for  their  untiring  labors. 

Illustrations  of  such  high  merit  deserved  to  be  associated 
with  reading-matter  of  corresponding  excellence,  and  I 
have  honestly  tried  to  produce  a  book  which  should  prove 
useful  and  stimulating  to  students  of  dentistry  as  well  as 
physicians  engaged  in  dental  practice.  If  I  have  failed  to 
realize  these  good  intentions  in  every  particular,  I  hope  to 
be  judged  with  some  indulgence  in  consideration  of  my 
many  duties  in  dispensary  and  private  practice,  which 
leave  me  little  time  and  opportunity  for  the  concentration 
so  necessary  to  literary  production. 

The  subject  of  laboratory  technic  has  been  omitted,  as  it 
does  not  properly  belong  in  a  "Medical  Atlas." 

GUST.  PEEISWERK-MAGrGI. 


LIST  OF  LITHOGRAPHIC  PLATES 


Plate  1 

Plate  2 

Plate  3 

Plate  4 


Plate  5. 


Plate  6. 
Plate  7. 
Plate  S. 


Plate  9. 

Plate  10. 
Plate  11. 


Plate  12. 
Plate  13. 

Fi; 

Plate  14.— Fi,< 
Fij 
Plate  lo.- 
Plate  1G.- 
Plate  1  T.- 
Plate 1  S.- 
Plate 19. 
Plate  20. 


-Lower  Jaw  of  an  Adult. 
-The  Blood-vessels  and  Xei'ves  of  the  Teeth. 
-Metallic  Cast  of  Combined  Pneumatic  Cavities  of  Face. 
■  Fig.   1. — Lateral  View  of  the  Permanent  Teeth. 
Fig.  2. — Lateral  View  of  the  Milk  or  Temporary  Teeth. 
-Fig.  1. — Longitudinal  Section  of  a  Tooth-root  and  theAlve- 

olus. 
Fig.  2.— Cross  Section  of  the  Oral  Mucous  Membrane. 
-Histologic  Preparations  of  the  Pulp. 

-Distribution  of  the  Blood-vessels  of  a  Young  Cuspid  Tooth. 
-Fig.  1. — Section  through  the  Border  between  the  Dentin 

and  the  Palp. 
Fig.  2. — Network  of  the  Connective  Tissue  in  the  Embiy- 

onal  Dental  Papilla. 
Fig.  3. — Ameloblasts  (Enamel  Constructors)  in  Activity. 
Fig.  4. — Isolated  Odontoblasts  (Dentin  Constructors). 
-Frontal  Section  through  the  Head  of  a  New-born  Child. 
-Tooth-germ  in  Diflerent  Stages. 
-Fig.  1.— Tooth-germ  of  a  Young  Cat. 
Fig.   2. — Secondary  Tooth-germ  of  a  Young  Cat. 
Fig.  3. — A  Section  of  Tooth-germ  Showing  Layei-s. 
-Tooth  Fragment  from  a  Deciduous  Canine  Tooth. 
-Fig.  a. — Typhoid  LHcer  on  the   Anterior  Surface  of  the 
Anterior  Palatine  Arch. 
h. — Mercurial  Stomatitis. 
1. — Periosteal  Cysts. 
2.— Follicular  Cyst. 
]\licroscopic  Preparation  of  the  Root  Fungosity. 
Prognathism. 
Prognathism. 
Mordex  Apertus. 
Enamel  Hypoplasise. 
Enamel  Hypoplaslae. 

9 


10  LIST  OF  LITHOGRAPHIC  PLATES. 

Plate  21. — Fig.  1. — Showing  a  Cuspid  Tooth  from  the  Upper  Surface 
of  Which  the  Enamel  Has  Disappeared. 
Fig.  2.— A  Molar  Tooth  of  an  Older  Man,  Which  Has 

Been  Worn  Away  by  Mastication. 
Fig.  3.— A  Middle  Incisor  Tooth  Which  Has  Been  Dis- 
colored Dark-brown  by  Extravasation  of  Blood. 
Figs.  4,  5,  and  6. — Brown  and  Green  Tooth  Deposits. 
Plate  22. — Carious  Molar  Tooth  the  Pulp  of  Which  is  Alive. 
Plate  23. — Carious  Molar  Tooth  the  Pulp  of  Which  is  Dead. 
Plate  24. — Application  of  the  Rubber  Dam  and  Other  Appliances  of 

Assistance  in  Deep  Caries  of  the  Front  Teeth. 
Plate  25. — Fig.  1. — Bicuspid  Tooth  with  Normal  Healthy  Pulp. 
Fig.  2. — Molar  with  Acute  Superficial  Pulpitis. 
Fig.  3. — Incisor  Tooth  with  Acute  Partial  Pulpitis. 
Fig.  4.— Molar  Tooth  with  Acute  Total  Pulpitis. 
Fig.  5. — Bicuspid  Tooth  with  Partial  Purulent  Pulpitis. 
Fig.  6.  — Molar  Tooth  with  Traumatic  Pulpitis. 
Plate  26. — Fig.  1. — Bicuspid  with  Gangrene  of  the  Pulp. 

Fig.  2. — Molar  with  Chronic  Hypertrophic  Sarcomatous 

Pulpitis. 
Fig.  3. — Incisor  with  Chronic  Hypertrophic  Granuloma- 
tous Pulpitis. 
Fig.  4. — Incisor  with  Chronic  Total  Purulent  Pulpitis. 
Fig.  5. — Bicuspid  with  Ascending  Pulpitis. 
Fig.  6. — W^isdom    Tooth    with  Chronic    Parenchymatous 
Pulpitis. 
Plate  27. — Fig.  1. — Incisor  Tooth  with  Atrophy  of  the  Pulp. 

Fig.  2. — Bicuspid  Tooth  with  a  Chronic  Total  Purulent 

Pulpitis. 
Fig.  3. — Incisor  Tooth  with  Idiopathic   or   Concretional 

Pulpitis. 
Fig.  4. — Molar  Tooth  with  Ascending  Gangrene  of  the 
Pulp. 
Plate  28. — Acute  Partial  Pulpitis. 
Plate  29. — Chronic  Pulpitis. 
Plate  30. — Abscess  of  the  Pulp. 
Plate  31. — Fatty  Degeneration. 
Plate  32.— Reticular  Atrophy  Caused  by  the  Hydremic  Degeneration 

of  the  Pulp  Elements. 
Plate  33. — Large  Concretions  of  Lime  Which  Have  a  Layer  Foi-ma- 
tion  Like  that  of  an  Onion. 


LIST  OF  LITHOGRAPHIC  PLATES.  11 

Plate  34. — Small  Concretions  of  Lnne. 
Plate  35. — Deposits  of  Lime. 
Plate  36. — Hyaline  Degeneration  of  the  Pulp. 
Plate  37. — A  Senile  Sclerotic  Pulp. 

Plate  38. — Demonstration  of  the  Amputation  of  the  Pulp  on  a  Longi- 
tudinally Cut  Molar. 
Plate  39. — Fig.  1. — Acute  Marginal  Periodontitis. 
Fig.  2.— Acute  Apical  Periodontitis. 
Fig.  3. — Acute  Circumscribed  Periodontitis. 
Figs.  4  and  5. — Acute  Unilateral  Periodontitis. 
Fig.  6. — Chronic  Difl'use  Purulent  Periodontitis. 
1. — Acute  Purulent  Periodontitis. 
2.  —Hypertrophic  Periodontitis. 
3. — Apical  Necrosis. 
4. — Total  Necrosis. 
.  5  and  6. — Interradicular  Abscess. 
1.— Fistula. 

2. — Alveolar  Pyorrhea. 
1. — Subperiosteal  Abscess. 
Fig.  2. — Blind  Abscess. 
Plate  43. — Periosteal  Abscess. 

Plate  44. — Fig.   1. — Toxic  Periodontitis  due  to  Arsenic. 
Fig.  2. — Beginning  of  Necrosis  of  the  Bone. 


Plate  40.- 

-Fig. 

Fig. 

Fig. 

Fig. 

Figs 

Plate  4L- 

-Fig. 

Fig. 

Plate  42.- 

-Fig. 

CONTENTS 

PAGE 

Historical 1" 

Comparative  Anatomy  of  the  Teeth      21 

Anatomy -^ 

The  Oral  Cavity  Externally 29 

The  Oral  Vestibule 30 

The  Oi-al  Cavity 33 

The  Upper  Jaw  (Maxilla) 41 

The  Inferior  Maxilla 4-1 

The  Blood-vessels  and  Nerves  of  the  Teeth 48 

Corrosion  Anatomy  of  the  Teeth  and  the  PNEt™ atio  Cavi- 
ties OF  THE  Face 51 

Corrosion  Anatomy  of  the  Teeth 51 

Corrosion  Anatomy  of  the  Pneumatic  Cavities  of  the  Face    .  54 

Special  Anatomy  of  the  Teeth 55 

The  Permanent  Teeth • 56 

The  Deciduous  Teeth 64 

The  Articulation  of  the  Teeth 65 

Histology  .  , 67 

The  Mucous  Membrane  of  the  Mouth 67 

The  Hard  and  Soft  Dental  Tissues 69 

PlIYSIOLOCiY 82 

The  Development  of  the  Teeth 82 

The  Development  of  the  Eoot 88 

Calcification  of  the  Deciduous  Teeth 89 

Eruption  of  the  Deciduous  Teeth 90 

Disturbances  Accompanying  Eruption  of  the  Teeth    ....    91 

The  Resorption  of  the  Deciduous  Teeth 94 

Calcification  of  the  Permanent  Teeth 99 

Eruption  of  the  Permanent  Teeth 99 

Location  of  the  Permanent  Crowns  before  the  Absorption  of 

the  Deciduous  Teeth  Roots 101 

Bacteriology 102 

Morphology  and  Biology 103 

The  Pathogenic  Action  of  Bacteria 109 

Staining  Methods 110 

13 


14  COXTENTS. 

Diseases  of  the  MoriH       113 

Catarrhal  Stomatitis 113 

Ulcerative  Stomatitis 115 

Decubital  Ulcers 117 

Aphthous  Stomatitis 117 

Mycotic  Stomatitis 118 

Actinomycosis 119 

Noma 121 

Pyorrhoea  Alveolaris  and  Atrophia  Alveolaris  Prtecox     .    .122 

Parotitis  (Mumps) 126 

Syphilis        126 

Tuberculosis 129 

TuMOES  OF  THE  Oeae  Cavity 130 

Benign  Growths • 130 

Cysts 130 

Fibroma 137 

Chondroma  and  Osteoma 139 

Lipoma .   ,    ,    .  141 

Malignant  Growths 141 

Sarcoma 141 

Carcinoma 142 

Growths  of  the  Hard  Dental  Substances 146 

Fractures  of  the  Lower  a:st>  the  Upper  Jaws •  148 

Dislocation  of  the  Lower  Jaw 1 54 

Empyema  of  the  Antrum  of  Highmore 155 

Acquired  and  Congenital  Defect.s  of  the  Face 163 

Anomalies  of  the  Teeth  and  the  Jaws 174 

Anomalies  of  Form  in  Individual  Teeth 177 

Anomalies  of  Position  of  Individual  Teeth 179 

Supernumerary  Teeth.     An  Insufficient  Number  of  Teeth    .  182 
Anomalies  of  the  Whole  Tooth  Row  with  and  without  Changes 

in  the  Jaw 184 

Dental  Deposits 190 

Congenital  Defects  of  the  Hard  Tooth  Substances   .    .    .    .192 
Acquired  Defects  of  the  Hard  Tooth  Substances   .....  195 

Physiologic  Abrasion  of  Tooth  vSubstances 195 

AVedge-shaped  Defects '   ...  197 

Defects  of  the  Labial  (Buccal)  and  the  Masticating  Surfaces 

of  the  Teeth 201 

Caries  of  the  Teeth    .    .    .    .    ; •  ...  201 

The  Zones  of  Caries 214 


CONTENTS.  15 

Treatment  of  Defects  of  the  Teeth 217 

The  Treatment  of  Tooth  Defects  by  Filling  and  the  Use  of 

Nitrate  of  Silver 218 

The  Filling  of  Teeth 220 

Filling  Materials 220 

The  Technic  of  Fillixg  of  Teeth 225 

Examination  of  the  Teeth 225 

Sei^arating  the  Teeth 226 

Drying  the  Cavities 229 

Preparation  of  Cavities 231 

Localization  of  the  Teeth 237 

Matrices 238 

Filling  with  Non-cohesive  Gold    .  .       240 

Filling  with  Cohesive  Gold 242 

The  Finishing  of  Gold  Filling 250 

Amalgam  Fillings 252 

Cement  Fillings 255 

Porcelain  Fillings 255 

Guttapercha  Fillings 258 

Diseases  of  the  Pulp 259 

Hyperemia  of  the  Pulp 261 

Acute  Superficial  Pulpitis 262 

Acute  Partial,  Total,  and  Traumatic  Pulpitis 263 

Acute  Partial  Purulent  Pulpitis  and  Chronic  Total  Purulent 

Pulpitis 265 

Chronic  Parenchymatous  Pulpitis 265 

Chronic    Hypertrophic     Granulomatous   and   Sarcomatous 

Pulpitis 267 

Gangrene  of  the  Pulp 268 

Idiopathic  or  Concretional  Pulpitis 269 

Pathologic  and  Anatomic  Kemarks  Concerning  Diseases  of 

THE  Pulp 271 

Diagnosis  of  Pulp  Diseasf^ 275 

Treatment  of  Diseases  of  the  Pulp 276 

The  Application  of  a  Cap  to  the  Pulp 276 

The  Destruction  and  Extirpation  of  the  Pulp 277 

Amputation  of  the  Pulp 281 

Diseasesofthi:  Root-Membrane  (Periopontitis) 283 

Acute  Periodontitis 285 

Chronic  Periodontitis 287 

The  Course  of  Inflammation  of  the  P<)iii-;i!omhrane     .    .    .    .288 
Treatment  of  InHamraation  of  the  Root-membrane      ....  290 


16  CONTENTS. 

Extraction  of  Teeth „ 293 

Indications ....,.....,,...  293 

Contraindications 296 

The  Technic  of  Extraction 298 

Extraction  of  the  Upper  Teeth 299 

Extraction  of  the  Lower  Teeth 301 

Extraction  of  the  Upper  Incisor  and  Cuspid  Teeth 301 

Extraction  of  the  Lower  Incisor  and  Cuspid  Teeth 303 

Extraction  of  the  Upper  Bicuspids  and  Molars 303 

Extraction  of  the  Lower  Bicuspids  and  Molars  ....     .    .  305 

Extraction  of  Eoots ••....  306 

Extraction  of  Deciduous  Teeth   . 309 

Complications  during  and  after  Extraction 309 

Anesthesia 313 

Dentin  Anesthesia 317 

General  Anesthesia   ......    o 319 

Prepakatton  of  the  Mouth  fob  Artificial  Teeth   .....  323 
Index  .................   .........   .  327 


DENTISTRY. 


HISTORICAL. 

Referexces  in  literature  point  to  the  existence  of  a 
well  developed  form  of  dentistry  among  the  Egyptians, 
in  corroboration  of  which  we  are  referred  to  the  gold- 
filled  teeth  which  have  been  found  in  mummies.  This 
observation  is  not  convincing  as  the  Egyptians,  in  embalm- 
ing the  bodies  of  their  departed,  covered  the  tongue 
and  teeth  with  thin  gold  leaf  for  the  purpose  of 
preservation.  However,  examination  of  many  ancient 
skulls,  notably  an  Etruscan  skull,  exhibited  in  the  museum 
of  Orvieto,  give  evidence  of  early  dental  practice.  The 
famous  papyrus  of  Eber  gives  a  list  of  remedies  such  as 
liverroot,  dough,  honey  and  oil  which  are  indicated  in 
certain  dental  affections.  It  may  be  assumed  that  artificial 
teeth  were  used  in  those  ancient  days  from  the  fact  that  a 
favorite  mode  of  punishment  designed  to  bring  disgrace 
upon  the  culprit,  was  the  extraction  of  a  front  tooth. 
Therefore,  when  a  tooth  was  lost  through  accident  or 
disease,  to  avoid  this  disgrace  it  became  necessarv  to  resort 
to  the  employment  of  artificial  substitutes.  The  ancient 
Egyptians  were  skilled  mechanics  and  able  to  model  teeth 
from  wax,  wood  or  clay,  and  the  perishableness  of  this 
material  would  account  for  the  scarcity  of  proof  of 
ancient  dental  practice. 

AYe  learn  from  the  Bible  that  when  Moses  led  the 
chosen  people  through  the  wilderness  to  the  Holy  Land, 
he  was  obliged  to  issue  penal  and  hygienic  laws  to  protect 
the  people,  who  were  already  broken  in  health  from 
slavery,  from  the  ravaging  pestilences.  It  is  notable  that 
in  tliese  careful  regulations  concerning  the  nourishment, 
clothing  and  cleanliness  of  the  body,  no  mention  is  made 
2  17 


18  HISTORICAL. 

of  the  teeth.  I  can  only  account  for  this  by  the  supposi- 
tion that  the  old  Hebrews  had  perfect  teeth,  a  fact  possible 
considering  the  enormous  diiference  in  races  in  regard  to 
the  relative  frequency  of  caries.  We  must  not  conclude, 
however,  that  this  race  neglected  or  disregarded  their 
teeth,  for  Moses,  elsewhere  in  the  laws  speaks  thus, — 
"And  if  any  mischief  follow  then  thou  shalt  give  life  for 
life,  eye  for  eye,  tooth  for  tooth,  hand  for  hand,  foot  for 
foot,  burning  for  burning,  wound  for  wound.  And  if  a 
man  smite  the  eye  of  his  servant  or  the  eye  of  his  maid 
that  it  perish  ;  he  shall  let  him  go  free  for  his  eye's  sake. 
And  if  he  smite  out  his  man-servant's  tooth,  or  his  maid- 
servant's tooth,  he  shall  let  him  go  free  for  his  tooth's 
sake." 

It  is  indeed  wonderful  that  so  much  importance  was 
attached  at  that  time  to  a  complete  set  of  teeth,  in  as 
much  as  the  loss  of  a  tooth  was  judged  equal  to  the  loss 
of  an  eye.  Not  until  thousands  of  years  later,  did  man 
realize  the  eminent  importance  of  teeth  for  the  body 
economy.  The  ancient  Greeks,  if  one  may  judge  from 
the  sparse  literature  of  their  time,  seem  to  have  possessed 
better  teeth  than  the  Egyptians.  Their  methods  for  the 
relief  of  toothache  were  very  primitive  and  consisted  in 
the  fasting  of  the  patient  and  in  the  worship  of  their 
gods.  They  also  sought  to  alleviate  their  dental  pains 
through  various  sleight  of  hand  tricks  and  music. 

With  Hippocrates  (460-355  b.  c.)  began  a  great  revolu- 
tion in  both  medicine  and  dentistry  and  it  is  highly  prob- 
able that  the  first  reform  in  the  latter  consisted  largely  in 
the  extraction  of  teeth.  It  seems  that  only  loose  teeth 
were  drawn  at  that  time  since  in  the  Temple  of  Delphi 
a  pair  of  forceps  were  found  which  being  made  of  lead 
could  not  possibly  have  been  employed  for  the  extraction 
of  soundly  imbedded  teeth.  Hippocrates  already  at  that 
time  laid  great  stress  upon  cleanliness  of  teeth  and  pre- 
scribed the  following  powder,  which  had  perhaps  a  mysti- 
cal as  well  as  a  physical  eifect :  "A  charmed  rabbit's  head 
and  three  charmed  mice  ground  into  a  powder."  He 
recognized  various  dental  affections  with  serious  sequellse 


HISTORICAL.  19 

resulting  from  neglect  of  the  teeth  and  writes  as  follows : 
''If  gangrene  of  the  teeth  be  accompanied  by  fever  and 
delirium  the  result  is  fatal.  If,  however,  the  patient 
should  recover  ulceration  remains  and  the  bone  is 
destroyed."  He  illustrates  the  story  by  the  following 
case, — The  son  of  the  Metrodor  developed  acute  gangrene 
of  the  jaw  after  a  toothache.  The  swelling  of  the  gums 
became  purulent  and  the  teeth  and  the  bone  were  destroved. 

The  oldest  information  on  Roman  dentistry  is  found  in 
the  laws  of  the  Twelfth  Tablet  which  states  :  "Add  no 
gold  to  the  corpse,  but  if  the  teeth  be  already  bound  with 
gold,  it  is  not  unlawful  to  bury  or  burn  the  body." 

According  to  Geist-Jakobi  we  find  the  founder  of 
dentistry  among  the  ancient  Romans,  namely,  the 
learned  Cornelius  Celsus  "svho  lived  at  the  time  of  Christ, 
In  his  celebrated  Avork  "  Re  de  ]\Iedica "  he  devoted 
certain  articles  to  the  pathology  and  therapy  of  teeth, 
subjects  which  at  one  time  were  combined  with  general 
medicine.  He  was  perhaps  the  first  to  practice  the  fill- 
ing of  carious  teeth.  He  inserted  in  the  cavity  pieces  of 
slate  wrapped  in  cotton,  endeavoring  thus  to  check  the 
caries.  The  cause  of  caries  was  sought  for  even  at  that 
time,  and  Scribonius  Largus  (50  A.  d.)  advances  the 
theory  that  M'orms  destroyed  the  substance  of  the  teeth. 
Hence  the  parasitic  theory  reaches  back  to  that  age. 

A  true  investigator  of  the  combined  medical  and  dental 
science  was  Claudius  Galenus  (131-200  A,  D,),  This 
skilled  physician  of  that  ancient  age  presented  some  new 
and  accurate  observations  on  the  anatomy  and  pathology 
of  the  teeth.  He  accurately  differentiated  between  disease 
of  the  pulp  and  that  of  the  root-membrane.  He  reports 
from  personal  observation  that  in  a  painful  tooth  he  plainly 
felt  a  pulsation  like  that  which  occurs  on  inflammation  of 
soft  tissues,  and  was  "surprised  that  a  tooth  also  could 
become  inflamed,"  Further  he  says:  "When  I  again  had 
toothache  I  realized  that  not  the  tooth  but  the  inflamed 
gum  was  the  cause.  From  Mhich  observations  I  learned 
that  a  certain  pain  may  have  its  seat  in  the  tooth  and 
another  in  the  jrum," 


20  HISTORICAL. 

For  the  preservation  of  the  teeth  Galen  prescribed  a 
large  number  of  tooth  powders  and  mouth  washes.  In 
the  middle  ages  when  culture  suffered  retrograde  changes 
in  Greece  and  Rome,  science  received  contributions  from 
the  Arabians.  In  our  specialty,  however,  this  did  not 
amount  to  much.  Dental  therapeutics  were  thus  enriched 
by  adopting  Abulkasa's  method  of  checking  the  toothache 
by  means  of  a  hot  iron  with  which  he  probably  cauterized 
the  pulp,  and  by  employing  arsenic. 

If  we  desire  to  learn  of  more  modern  and  practical 
results,  we  must  return  to  Italy  where  in  the  year  of 
1500,  Johannes  Arculanus  energetically  recommended  the 
conservative  treatment  of  diseased  teeth.  He  was  the 
first  to  fill  teeth  with  gold  for  the  sake  of  preserving 
them. 

Dentistry  received  a  marked  impetus  at  the  end  of  the 
sixteenth  century  through  Ryff  who  wrote  a  book,  divided 
iuto  the  following  parts  :  1 — The  eyes.  2 — The  teeth.  3 
— The  teeth  of  suclvling  infants.  In  this  treatise  he  called 
attention  to  the  relationship  existing  between  diseases  of 
the  teeth  and  the  eyes,  and  the  effects  of  decayed  teeth 
upon  the  general  health  of  the  organism.  With  com- 
mendable foresight  and  energy  he  urged  the  people  to 
observe  the  laws  of  hygiene  and  especially  those  which 
concerned  the  thorough  care  of  the  teeth. 

Eustachius,  who  lived  in  Hyff 's  time  is  closely  associ- 
ated with  the  embryology  and  anatomy  of  teeth.  He 
taught  that  the  tooth  was  developed  from  a  dental  sac, 
and  that  the  second  or  permanent  teeth  were  developed 
from  special  germs  and  not  from  the  roots  of  the  tempo- 
rary set.  He  described  a  number  of  the  elements  of  a  tooth 
and  called  attention  to  the  enamel,  -which  covers  the 
dentine  like  a  bark,  and  stated  that  the  interior  of  the 
tooth  was  filled  with  a  pulp,  richly  supplied  with  nerves. 
He  also  wrote  on  the  anomalies  of  teeth  and  described 
a  case  of  fourth  dentition.  It  is  impossible  to  describe 
in  detail  the  investigation  of  the  remaining  earlier 
authorities  in  dentistry,  but  I  wish  to  make  mention  of 
the  most  important  ones.      Highmore  (1613-1684)  dis- 


COMPARATIVE  A2J ATOMY  OF  THE  TEETH.        21 

covered  that  the  superior  maxilla  was  a  hollow  instead  of 
a  solid  bone.  Leeuwenhoek  (1632-1723)  by  various 
improvements  in  the  microscope  made  considerable  pro- 
gress in  dental  histology. 

A  decided  advancement  was  made  in  1800,  in  Frank- 
fort through  Fauchard,  who  is  everywhere  honored  as 
the  father  of  modern  dentistry.  In  his  epoch  making 
work  of  1728,  "  Le  Chirurgien  Dentiste  ou  traite  des 
dents,"  he  laid  the  foundation  for  the  anatomy,  physiology, 
pathologv,  and  therapy  of  the  mouth  and  teeth.  Founded 
on  these  fundamentals,  there  has  arisen  a  massive  structure, 
the  materials  of  which  have  been  collected  from  all  the 
civilized  lands  of  the  world,  the  structure  of  the  well 
established,  although  not  yet  complete  international  science 
of  dentistry. 

COMPARATIVE  ANATOMY  OF  THE  TEETH. 

We  must  not  neglect  a  review  of  the  most  important 
forms  of  mammalian  teeth,  as  their  relationship  to  the 
whole  skeletal  structure  is  of  considerable  scientific  import- 
ance. That  in  doing  so  we  shall  be  forced  to  resort  to 
paleontology  and  to  go  back  to  fossil  teeth  as  the  sole 
remains  of  an  extinct  fauna,  is  rather  an  advantage  than 
otherwise,  for  the  scientific  odontologist  should  not  be 
ignorant  of  paleontology. 

The  teeth  of  all  mammalia,  are  formed  in  the  mucous 
membrane  of  the  mouth  ;  as  their  development  progresses 
the  alveolar  processes  of  both  jaws  grow  about  the  teeth 
thus  bringing  them  in  close  connection  with  the  skull. 
They  are,  however,  never  joined  to  the  skull  by  a  firm 
bonv  growth,  for  a  layer  of  connective-tissue  always 
remains  between  the  roots  of  the  tooth  and  the  bony 
structure. 

The  teeth  of  the  majority  of  the  mammals  consist  of 
enamel,  dentin,  and  cement.  They  are  hollow  within 
and  contain  the  tooth  pulp  or  marrow.  The  enamel  is 
a  hard  substance  which  usually  covers  the  crown  com- 
pletely.    Exceptions  to  this  rule  are  seen  in  the  incisor 


22       COMPARATIVE  ANATOMY  OF  THE  TEETH. 


teeth  of  rodents  of  the  proboscidian  type,  in  which  only 
the  anterior  surface  is  protected  by  enamel,  and  also  in 
the  toothless  edentata  in  which  the  enamel  is  never 
perfectly  developed.  Dentin,  the  main  part  of  the  tooth, 
consists  of  a  more  or  less  solid  substance  giving  the  typ- 
ical form  to  the  tooth,  and  encloses  the  pulp.  The  roots 
are  covered  with  a  thin  layer  of  cement,  which  is  the 
softest  of  the  three  hard  dental  substances. 

In  many  of  the  mammals,  especially  the  herbivora, 
this  cement  extends  over  the  crown  of  the  tooth  and  is 
called  the  crown-cement. 

If  the  crown  of  the  tooth  is  low,  roots  are  developed 
which  contain  the  pulp  in  their  narrow  apical  foramina  : 
such  teeth  are  termed  brachyodont.  If  a  tooth  is  long 
and  of  cylindrical  shape  with  w^ide 
root  canals  it  is  called  hypsodont. 
The  human  molar  (Fig.  1,  u)  is  an 
example  of  the  former  and  the  molar 
of  a  horse  an  example  of  the  latter 
(Fig.  1,  h).  According  to  their 
physiological  functions,  teeth  assume 
certain  characteristic  shapes.  Com- 
plete absence  of  teeth  occurs  only  in 
those  animals  which  are  not  required 
to  cut  their  food  into  small  pieces,  as 
the  cetacea,  the  anteater,  and  the  duck- 
Pie.  1.  billed  platypus.    Animals  which  need 

only  to  seize  and  retain  their  food  are 
furnished  with  simple  teeth  all  of  which  are  alike  in  form. 
This  is  the  "isodont"  type  of  tooth,  and  is  found  in  the 
sea  mammals  (toothed  M^hales  and  the  delphinus). 

The  majority  of  mammals  possess  anisodontous  teeth, 
the  shape  of  which  depends  upon  their  situation  in  the 
jaw  and  upon  the  special  functions  they  are  required  to 
perform.  The  function  of  the  front  part  of  the  mouth  is 
to  secure  and  sever  the  food,  therefore,  the  teeth  in  this 
location  are  usually  sharp,  while  the  teeth  in  the  back 
portion  of  the  mouth  have  a  flat  wide  surface  for  the 
purpose  of  crushing  and  grinding  the  food. 


COMPARATIVE  ANATOMY  OF  THE  TEETH.       23 

Aside  from  the  function  of  acquisition  and  mastication 
of  food,  teeth  serve  occasionally  for  other  purposes.  It  is 
known  for  instance  that  the  stallion  has  a  hook  tooth 
which  is  not  found  in  the  mare.  A  similar  condition  is 
found  in  musk  deer.  His  teeth  are  his  strongest  weapon  and 
he  employs  them  to  defend  his  mate.  According  to  the  laws 
of  reciprocal  relation,  the  canine  teeth  of  the  horned  deer 
decreases  in  size  as  the  horns  grow  larger,  until  tinally  the 
function  of  defense  is  transferred  from  the  teeth  to  the 
horns.  Animals  must  frequently  remove  obstructions 
from  their  paths,  for  this  purpose  they  are  supplied  with 
long  projecting  tusks.  Such  animals  are  the  mammoth, 
the  elephant,  the  walrus,  the  hippopotamus  and  the 
male  narwhal,  which  also  uses  them  in  defense  when 
rutting^. 

According  to  the  demands  made  upon  them  the  incisor 
teeth  present  many  variations  in  form.  To  fulfill  their 
function  the  incisors  of  all  gnaM'ing  animals  are  consider- 
ably elongated.  They  are  somewhat  curved  and  in  order 
to^  have  sharp  edges,  only  the  front  surface  is  covered 
with  enamel.  To  this  class  belong  the  majority  of  the 
rodents,  tillodonts,  allotherise,  and  the  diprotodontic  ani- 
mals of  prey.  The  before  mentioned  tusks  of  tiie 
elephant  and  narwhal  are  also  differentiated  forms  of 
incisors.  In  pigs  the  lower  incisors  grow  horizontally 
upward  and  forward,  a  formation  necessary  to  grub 
nourishing  roots,  while  the  lower  incisors  of  certain 
members  of  the  lemuridous  tribe  of  monkeys  are  finely 
niched  that  they  may  be  used  as  combs  in  their  daily 
toilette.  The  sirenia  are  characterized  by  large  upper 
incisor  teeth  with  which  they ,  pull  up  Various  water 
plants  for  their  nourishment. 

When  an  incisor  tooth  develops  excessively  in  size,  the 
remaining  incisors  are  usually  fewer  in  number.  Hence 
we  may  find  tliat  in  many  animals  of  the  proboscidian 
type,  the  lower  incisors  have  completely  disappeared. 
This  phenomena  may  occur,  however,  in  the  absence  of 
such  a  condition,  for  example  we  know  that  the  ruminantia, 
the  dinocerata  and   the    chalicotheridse,   have  no   upper 


24       COMPARATIVE  ANATOMY  OF  THE  TEETH. 


Fig.  2. 


incisors,  while  iu  the  majority  of  the  edentata  both  upper 
and  lower  incisors  fail  to  develop. 

The    molar    teeth   are    divided 
into : 

1.  Teeth  with  sharp  points  and 
edges  (secodont)  Fig.  2,  a. 

2.  Cusped  teeth  (biinodont)  Fig. 

3.  Teeth  with  straight  crests  of 
enamel  (lophodont)  Fig.  2,  c. 

4.  Teeth  with  crescentic  ridges 
on  their  crowns  (selenodont)  Fig. 
2,  d.  An  example  of  the  secodont 
tooth  is  the  molar  of  the  beast  of 
prey,  and  is  found  iu  animals  which 
are  required  to  sever  and  tear  their 
food  into  pieces  (carnivora,  marsu- 
pialia,  chiroptera,  insectivora).  The 
molars  of  the  insectivora  are  ap- 
proximately of  this  type.  Meat  nourishment  is  easily 
digested  and  hence  the  whole  alimentary  tract  of  these 
animals  is  very  simple  in  construction.  In  carnivora, 
whose  dental  crowns  are  narrow  and  provided  with  sharp 
horizontal  edges,  the  intestinal  canal  is  but  from  three  to 
five  times  as  long  as  the  body,  while  the  herbivorous  ani- 
mals possess  an  intestinal  canal  twenty  times  as  long  as 
their  body. 

Bunodont,  or  humjjed  teeth  are  found  in  the  fruit  eaters 
and  the  omnivora.  The  nutritious  value  of  fruit  is  much 
less  than  that  of  meat,  therefore,  the  alimentary  system 
of  such  animals  is  more  complicated.  Their  molars  are 
wider,  supplied  with  cusps  and  shorter  than  the  other 
types.  The  dental  apparatus  of  the  fruit-devouring  mon- 
key resembles  decidedly  that  of  the  human  being,  on 
account  of  which  many  investigators,  among  them  Baume, 
concluded  that  fruit  formed  the  priuiitive  nourishment 
of  man.  Although  the  human  teeth,  with  reference  to  the 
shape  of  the  molars,  indicate  fruit  as  the  main  article  of 
diet,  yet  the  length  of  the  human  intestines  argues  against 


COMPARATIVE  ANATOMY  OF  THE  TEETH.        25 

this  supposition.  In  frugivorous  monkeys,  the  intestinal 
canal  measures  ten  times  the  body  length  while  that  of 
man  equals  only  five  to  six  times  its  length,  therefore,  the 
human  being  inclines  toward  caruivorism.  Baume  argued 
against  this  theory  as  follows  :  "  The  intestine  of  man  is 
k^ss  developed  than  that  of  the  frugivorous  animals 
because  it  has  less  heavy  work  to  perform.  Man,  indeed, 
eats  fruit,  but  he  avoids  those  fruits  which,  on  account  of 
their  indigestibility,  require  a  larger  alimentary  apparatus. 
He,  therefore,  ingests  in  much  smaller  quantities  those 
foods  which  are  of  less  nutritive  value  than  meats.  Hence 
it  may  be  concluded  that  increased  development  in  the 
size  of  the  intestines  is  dependent  upon  the  bulk  of  the 
ingested  food." 

According  to  his  tlieory  then  the  length  of  the  intestinal 
canal  was  reduced  as  a  result,  secondary  to  the  use  of  meat 
as  a  nourishment.  I  cannot  wholly  agree  with  this  obser- 
vation. Although  there  are  reasons  to  believe  that  Me  may 
inherit,  to  a  certain  extent,  various  parts  of  the  body 
Avhich  have  atrophied  through  disease,  yet  the  intestines 
possess  such  old  evohitional  characteristics  that  it  is  hard 
to  believe  that  the  intestinal  tract  could  have  become 
so  considerably  shortened.  I  have  in  mind  the  CEecum 
which  has  been  carried  doMn  to  us  from  our  most  distant 
ancestors  and  which  might  have  been  eliminated  long  ago. 
Before  we  can  assume  that  the  length  of  the  intestinal 
tract  is  influenced  by  the  nature  of  the  food,  we  must 
experimentally  attempt  to  reduce  the  length  of  the 
intestines  of  a  monkey  in  captivity  by  feeding  him  meat. 
Such  experiments,  however,  are  hardly  practicable  as  they 
would  have  to  be  continued  for  a  long  period  of  time. 

I  do  not  believe  that  we  Mould  obtain  a  positive  result 
for  if  Baume's  theory  held  true  decided  diflPerenccs  M'ould 
exist  betM'een  the  intestines  of  poor  peasants  and  those  of 
the  meat  eating  city  inhabitants,  the  former  liaving  existed 
for  generations  upon  field  and  milk  products  and  only  on 
Sunday  olitained  a  small  portion  of  bacon.  Such  a 
difference,  hoMever,  has  never  })een  found:  on  the  con- 
trary, the  linear  intestinal  dimension  of  the  human  being 


26        COMPARATIVE  ANATOMY  OF  THE  TEETH. 

is  always  about  eight  meters  or  from  five  to  six  times  the 
body  length.  Therefore  man,  because  of  his  bunodont, 
frugivorous  set  of  teeth  and  his  carnivorous  intestines 
belongs  to  the  same  class  as  did  his  ancestors,  namely,  the 
omnivora. 

The  motion  of  the  jaws,  in  mastication,  in  the  carnivora 
as  well  as  in  the  insectivora  and  omnivora  is  vertical, 
from  below  upward. 

The  nutrititious  value  of  vegetables  is  less  than  that  of 
fruits,  and  in  order  to  extract  it,  the  molars  of  the  herbivora 
are  more  complicated  in  form.  Jn  the  lophodont  mammals, 
of  which  the  best  representatives  are  the  now  extinct 
lophiodon  and  the  extinct  tapir,  the  cusps  are  united  by 
arches  which  enables  them  to  grind  the  food  more  easily 
than  the  bunodont  type  of  tooth  with  its  less  complicated 
pattern.  When  the  arches  are  concentric  in  shape,  as  in 
many  of  the  ruminants  they  are  called  selenodont  teeth. 
The  position  of  these  arches  varies  with  the  movements 
of  the  inferior  maxilla  in  such  a  way  as  to  be  perpendic- 
ular to  the  direction  of  movement.  Accordingly  the 
enameled  plates  of  the  teeth  of  the  ruminants,  in  cen- 
trifugal and  centripetal  mastication,  lie  obliquely  to  the 
longitudinal  plane  of  the  alveolar  process.  In  the  gnaw- 
ing animals  the  inferior  maxilla  glides  from  in  front  back-, 
ward  (proal)  and  accordingly  the  arches  lie  transversely 
to  the  longitudinal  axis  of  the  alveolar  process.  The 
latter  is  also  true  of  the  proboscidea  (of  which  the  elephant 
is  a  good  example)  in  which  the  mastication  is  palinal, 
that  is  from  behind  forward.  In  these  cases  we  do  not 
find  a  transversely,  but  a  longitudinally  set  condyl  which 
slides  in  a  groove  at  the  base  of  the  temporal  bone.  The 
majority  of  the  mammals  have  two  sets  of  teeth  and  are 
therefore  called  diphyodont.  The  sirenia,  the  toothed 
whales  and  the  edentata  are  the  only  mammals  to  retain 
their  original  set  of  teeth  throughout  life,  during  which 
time  they  remain  useful.  Such  animals  are  therefore 
monophyodont.  When  primary  teeth  are  replaced  by  a 
n2w  set  of  teeth,  the  latter  is  composed  of  a  greater 
number,  and  larger  teeth  than  the  temporary  set. 


COMPARATIVE  ANATOMT  OF  THE  TEETH.        27 

According  to  Baiime  the  shortening  of  the  jaw  bone  in 
the  course  of  evolution  forces  the  milk  teeth  out  of  the 
tooth  row.  He  considers,  therefore,  the  milk  teeth  as  a 
part  of  the  permanent  set,  the  difference  being  only  one 
of  time.  Other  authorities  also  believe  that  the  diphyodont 
type,  that  is  having  a  milk  and  a  permanent  set  of  teeth, 
develops  from  the  monophyodont  type  and  that  this 
occurs  only  in  the  mammals. 

In  Zittel's  opinion,  with  which  I  agree,  it  has  not  been 
proven  that  the  diphyodont  mammals  are  developed  from 
the  monophyodont,  for  on  the  contrary  many  monophy- 
odont t}'pes  are  known  whose  predecessors  possessed  two 
sets  of  teeth.  As  examples  we  need  only  to  mention  the 
proboscidea,  many  of  the  rodents,  the  insectivora  and  the 
edentata,  in  all  of  whom  the  shedding  of  the  milk  teeth 
is  evidently  a  retrogressive  process  in  comparison  with 
that  of  their  ancestors.  According  to  the  important  con- 
tributions of  Kiickenthals  the  embryos  of  monophyodont 
mammals  very  often  possess  milk  tooth  germs  which, 
however,  never  reach  development  or  eruption.  Other 
observers,  among  them  KoUmann,  have  noticed  the  same 
occurrence  in  man.  In  this  case  it  is  supposed  that  the 
tooth  ledge  produces  supernumerary  milk  tooth  germs 
which,  however,  only  occasionally  develop  into  supernu- 
merary teeth.  We  hold  a  convincing  argument  against 
Baume's  theory,  if  it  is  concluded  from  the  above  state- 
ments and  from  the  observation  of  Riitimeyers  that  the 
milk  teeth  inherit  the  evolutionary  forms  of  their  ancestors 
and  what  seems  most  plausible  that  the  monophyodont 
forms  descend  from  the  diphyodont  and  perhaps  the 
diphyodont  from  polyphyodont.  Therefore,  from  the  per- 
petual shedding  of  milk  teeth,  which  for  example  is  ty])ical 
in  the  shark,  the  diphyodont  type  develops  and  from  it 
the  monophyodont  type.  Through  diifercntiation  and 
perhaps  occasional  retrogression  in  the  development  of 
tlie  individual  tooth  it  appears  that  the  number  of  sets  of 
teeth  become  constantly  smaller.  At  first  simple  teeth 
were  supplied  which  were  continually  shed,  tlien  wlien 
the  type  of  the  teeth  became  more  complex  nature  became 


28       COMPARATIVE  ANATOMY  OF  THE  TEETH. 

more  economical  in  this  respect,  until  finally  only  one  set 
of  teeth  developed.  We  may  feel  satisfied  then  that  man 
has  not  yet  arrived  at  the  final  stage  of  his  development 
for  he  has  still  to  look  forward  to  the  monophyodont 
state. 

All  of  the  various  types  of  teeth  may  blend  witli  one 
another  and  become  complicated  through  the  addition  of 
grooves  and  cusps  of  many  varieties.  Applying  this  law 
to  the  human  molar  we  may  look  upon  it  as  belonging  to 
the  bunodont  and  brochyodont  type.  The  human  dental 
apparatus  is  called  anisodont  because  of  the  difference 
between  the  incisors  and  the  molar  teeth,  a  characteristic 
which  it  shares  with  the  majority  of  the  mammals.  On  the 
other  hand  the  human  teeth  lie  in  juxtaposition  to  each 
other  and  form  rows  in  which  no  diastem  occurs,  an 
arrangement  which  not  many  animals  and  none  of  the 
primates  have  in  common  with  the  human  being.  With 
reference  to  the  shedding  of  his  milk  teeth,  man  is  con- 
sidered diphyodont,  and  according  to  the  movements  of 
mastication,  orthal. 

AYe  are  then  confronted  with  the  question  as  to  the 
nature  of  the  evolutional  changes  through  which  the  teeth 
pass  before  reaching  the  present  stage  of  high  differenti- 
ation. Those  investigators  who  accept  the  observations 
of  Lyell  and  Darwin  conclude  that  the  summing  up  of  all 
the  small  changes  which  occur  from  time  to  time  finally 
amount  to  enormous  differences  in  the  forms  of  all  living 
creatures  and  their  teeth.  There  exists  no  fixed  form,  no 
state  of  perpetuation,  in  nature ;  all  forms  of  life  is  either 
passing  into  or  out  of  existence. 

I  will  attempt  to  make  clear,  as  Cope  and  Osborn 
determined  by  mechanical  laws,  the  gradual  development 
of  mammalian  teeth  from  their  original  state.  As  a 
primitive  type  we  may  accept  the  simple  cone  tooth  (hap- 
lodout  type).  This  tooth  consists,  as  is  seen  for  example 
in  the  toothed  whales,  of  a  pointed  crown  with  a  simple 
elongated  root  (Fig.  3,  a). 

A  small  pointed  tip  develops  on  the  anterior  and  pos- 
terior sides  of  this  cone  shaped  tooth.     This  is  the  proto- 


ANATOMY. 


29 


dont  type  of  tooth  and  occurs  in  the  beasts  of  prey  of 
ancient  times.  In  the  course  of  time  these  tips  become 
large,  develop  into  a  tooth  having  a  strong  median  point 
with  two  accessory  weaker  points,  one  in  front  and  one 
behind,  which  is  called  the  triconodont  tooth  and  is  found 
in  the  mesozoic  beast  of  prey.  The  root  of  this  tooth  has 
two  branches  (Fig.  3,  h). 

In  the  fourth  stage  the  crown 
becomes  wider,  so  that  the  median 
cusp  no  longer  is  in  a  straight  line 
with  the  accessory  cusps  but  lies 
either  to  the  outer  or  inner  side  of 
it.  This  is  the  tritabercular  tooth 
(Fig.  3,  c).  Such  a  tooth  with 
three  tubercles  or  cusps  which  is 
only  seen  in  the  mesozoic  beasts  of 
prey,  develops  through  the  addition 
of  new  cusps  into  the  quadrituber- 
cular,  quinque-tubercular  the  sex- 
tubercular  and  finally  multituber- 
cular  tooth  which  is  found  in  the 
allotherise  (Fig.  3,  J). 

I  will  not  consider  in  further  detail  the  evolution  of 
teeth,  for  we  mav  easilv  imag-ine,  through  the  rearrano-e- 
ment  of  the  position  of  their  cusps  and  their  union 
through  arches  and  ridges,  how  the  modifications  are 
obtained,  which  exist  in  the  vertebrates  in  such  manifold 
forms. 


^ 


Fig.  3. 


ANATOMY. 
THE  ORAL  CAVITY  EXTERNALLY. 

"We  will  consider  the  topographical  anatomy  of  the  oral 
cavity,  for  it  is  assumed  that  tlie  reader  is  already 
acquainted  with  its  general  anatomy.  Externally  the 
oral  region  is  distinctly  outlined  from  the  neighboring 
structures  (Fig.  4).  Laterally  it  is  bounded"  by  the 
salens  na.solab talis  which  extends  from  the  ala  nasi  to  the 
angle  of  the  mouth ;  below  it  reaches  the  mentolabial  Jur- 


30  ANATOMY. 

FIGURE  4. 

Outer  surface  of  the  moutli. 
a.    The  nasolabial  sulcus,     h.  Labiomental  sulcus,    c.   The  philtrum. 

row  which  is  curved  convexly  upward,  and  above  it  extends 
to  the  nose.  These  grooves  or  furrows  are  more  sharply 
defined  in  the  old  than  in  the  young,  and  in  people,  who 
on  account  of  their  occupation,  are  required  to  open  their 
mouths  widely,  such  as  actors.  They  are  also  more 
marked  in  chronic  diseases. 

Normally  the  upper  lip  protrudes  slightly  more  than 
the  lower.  When  the  upper  lip  is  excessively  thickened 
it  is  often  indicative  of  a  scrofulous  condition  with 
adenoids  in  the  nasal  region.  If  the  lower  lip  protrudes 
abnormally  one  may  suspect  an  unusual  forward  ex- 
tension of  the  lower  row  of  teeth.  AVe  meet  quite 
frequently  in  practice,  cases  in  which  the  upper  lip 
is  so  short  that  during  conversation  the  gums  are  con- 
stantly visible.  This  results  in  a  chronic  local  irritation 
of  the  gums  in  this  location  through  the  thermic  and 
desiccant  influence  of  the  atmosphere,  especially  during 
the  night.  The  many  microorganisms  of  the  air  are 
deposited  on  the  mucous  membrane  as  well  as  on  the 
front  teeth  resulting  in  the  formation  of  a  destructive 
accumulation  on  the  anterior  surfaces  of  the  teeth,  espe- 
cially on  the  incisors. 

THE  ORAL  VESTIBULE. 

Back  of  the  outer  wall  of  the  mouth  and  the  cheeks 
lies  the  horseshoe  shaped  oral  vestibule  (Fig.  5,  a).  There 
exists  in  reality  usually  no  such  space,  for  the  mucous 
membrane  of  the  cheeks  rests  directly  upon  the  teeth  ; 
liut  tlirouL^h  inflation  one  may  determine  the  amount  of 
space  which  the  elasticity  of  the  outer  walls  permits  the 
vestibide  to  occupy.  Tliis  is  of  great  importance  in  the 
examination  and  treatment  of  dental  affections.  It  is 
curious  that  in  mastication  the  cheeks  do  not  collapse 
between  the  molar  teeth.  Henle  accoimts  for  this  by  the 
presence  of  a  firm  membrane  which  is  so  intertwined  with 


Fig.  4. 


THE  ORAL    VESTIBULE.  31 

the  buccinator  muscle  that  it  causes  the  mucous  membrane 
to  form  into  folds  thus  preventing  it  from  falling  between 
the  teeth  when  they  are  closed. 

The  fold  by  Merkel  the  "  fornix  "  which  consists  of  a 
layer  of  tissue  reflected  from  the  external  to  the  internal 


FiG.  5.— A  median  section  of  the  buiium  liead.    a.  The  oral  vestibule,    b.  The 

oral  cavity. 

Avails  of  the  vestibule,  has  the  greatest  amount  of  elasticity. 
The  mucous  mcmbraue  at  this  point  is  considerably  relaxed 
and  hangs  jjarticularly  low  on  the  superior  maxilla  between 


32  ANATOMY. 

the  bicuspid  and  molar  teeth.  In  front  a  tighter  fold  of 
the  mucosa,  called  the  frgenum,  connects  the  inner  with 
the  outer  wall  of  the  fornix,  in  both  the  upper  and  lower 
jaw.  In  the  practice  of  prosthetic  dentistry  this  relation- 
ship must  be  remembered  and  the  artificial  plate  cut 
accordingly.  To  one  side  of  the  posterior  part  of  the 
fornix,  the  coronoid  process  of  the  lower  jaw  may  be  felt. 
It  is  of  interest  because  it  may  occasionally  interfere  with 
the  application  of  the  coiferdam  clamps  to  the  second 
molars. 

Opposite  the  first  and  second  molars  one  notices  a  pin- 
head  sized  caruncle  which  is  pierced  by  a  fine  hair-like 
opening,  the  excretory  duct  {Stenson's  duct).  The 
parotid,  the  largest  of  the  salivary  glands,  lies  in  front 
and  below  the  ear  occupying  the  space  behind  the  ramus 
of  the  lower  jaw.  Its  largest  mass,  which  is  multilobul- 
ated,  lies  between  and  aroaud  the  muscles,  blood-vessels, 
nerves,  bony  prominences,  etc.  Posteriorly  it  is  bounded 
by  the  sternocleidomastoid  muscle  and  the  mastoid 
process ;  a  little  below  it  reaches  the.  digastric  muscle 
and  surrounds  the  styloid  process.  A  few  lobes  lie  also 
in  front  between  the  pterygoid  muscles.  Above  it  encloses 
the  temporo-maxillary  joint.  The  part  which  is  not 
covered  by  muscle  rests  on  the  zygomatic  process  and 
sends  a  wedge  shaped  thin  lobe  over  the  masseter  muscle. 

On  account  of  the  excessively  soft,  flabby  consistency 
of  the  gland  substance,  it  is  even  difficult  to  feel  by 
pressure  that  part  of  the  gland  which  is  lodged  against 
the  angle  of  the  jaw.  A  negative  observation  in  an 
emaciated  subject  is  much  more  satisfactory,  for  then  the 
angle  of  the  jaw  stands  forth  prominently,  and  between 
the  ear  and  the  ascending  ramus  of  the  maxilla  a  deep 
furrow  exists  due  to  the  disappearance  of  the  gland  sub- 
stance. 

In  chewing  ;md  speaking,  the  movable  parts,  that  is, 
the  lower  jaw  and  its  musculature  press  the  parotid  gland 
against  the  fixed  bony  parts,  so  that  it  is  flattened  like  a 
sponge.  When  the  mouth  is  held  quietly  open,  normally 
but   little  liquid  appears,  in  comparison  with  the  large 


THE  ORAL   CAVITY.  33 

size  of  the  gland.  Hence  in  short  dental  operations  the 
upper  jaw  may  be  kept  perfectly  dry  by  the  placing  of 
absorbing  materials  over  the  mouth  of  the  diict  of  Sten- 
son. 

Foreign  bodies,  especially  microorganisms  may  travel 
from  the  oral  cavity  through  the  excretory  duct  to  the 
parenclivma  of  the  parotid  gland.  Therefore  chronic 
swelling  of  this  gland  occurs  not  infrequently  in  con- 
sequence of  badly  neglected  teeth.  In  epidemic  parotitis 
the  infection  also  probably  effects  an  entrance  through  the 
oral  cavity. 

According  to  Tillmann^  inflammation  of  the  parotid 
gland  is  originally  caused  by  degenerative  changes  in  the 
secretion  of  the  mouth.  As  the  parotid  gland  is  enclosed 
on  all  sides  by  a  firm  fibrous  capsule,  which  is  thickest 
where  the  gland  lies  upon  the  muscles,  and,  as  it  is  also 
partially  enclosed  by  bony  walls,  a  slight  swelling  soon 
causes  pain  Avhich  the  patients  usually  attribute  to  the 
back  molars.  AVhen  the  movements  of  the  lower  jaw  are 
interfered  Avith,  patients  are  especially  inclined  to  con- 
sider the  third  molar  tooth  as  the  cause  of  the  truulde. 
To  establish  the  diagnosis  palpate  the  gland  externally,  and 
if  no  swelling  can  be  found  in  front  of  the  ear,  or  on  the 
masseter  muscle,  then  examine  the  submaxillary  angle, 
where  a  swelling  may  be  early  detected,  for  in  this  area 
according  toKonigthe  fibroid  capside  is  thinnest. 

THEORAL  CAVITY. 

Strictly  speaking  when  tlie  mouth  is  closed  tlie  oral 
cavitv  is  not  a  real  cavity  for  the  tongue  touches  the  walls 
on  all  sides  (Fig.  5)  excepting  at  its  posterior  end  where 
an  open  space  occurs  for  the  free  flow  of  liquids.  Even 
when  the  mouth  is  open  one  can  hardly  consider  it  a 
cavity,  for  being  in  direct  connection  with  the  pharynx  it 
forms  a  canal  rather  than  a  hollow  space.  Its  boundaries 
are  equally  uncertain  and  are  best  outlined  by  the  liard 
structures.     Hence  its  boundaries  in  front  are  formed  by 

^  Lelirbnch  cler  spez.  Chirurgie,  1S97,  page  42-i. 
3 


34  ANAT03IY. 

the  incisor  and  cuspid  teeth  and  laterally  by  the  molars. 
Above  it  is  limited  only  in  front  by  a  firm  structure,  the 
hard  palate,  while  further  back  is  the  soft  palate  which 
has  a  certain  amount  of  mobility. 

The  floor  of  the  oral  cavity  is  occupied  by  the  tongue. 
In  order  to  mark  the  point  or  better  the  surface,  where 
the  mouth  ends  and  the  throat  begins,  the  mylohyoid 
muscle  is  employed  as  the  anatomical  boundary.  As  is 
well  known,  this  muscle  stretches  diaphragmatically 
between  the  rami  of  the  inferior  maxillary  and  the  hyoid 
bone.  That  is,  it  arises  from  the  mylohyoid  line  which 
runs  diagonally  from  the  upper  posterior  end  to  the  lower 
anterior  end  of  the  inferior  maxilla.  The  majority  of 
the  muscle  bands  run  to  the  median  fibrous  raphe  which 
extends  from  the  symphysis  of  the  lower  jaw  to  the  hyoid 
bone.  The  smaller  part  of  this  muscle  inserts  directly 
into  the  body  of  the  hyoid  bone. 

Posteriorly  the  oral  cavity  reaches  to  an  imaginary 
plane  which  is  drawn  between  the  palatine  arches,  the  so- 
called  isthnms  of  the  fauces.  We  will  only  consider  in 
detail  here  the  anatomical  structures  of  the  mouth  which- 
do  not  stand  in  close  relationship  with  the  teeth,  the 
anatomy  of  which  will  receive  especial  attention  else- 
where. 

The  roof  of  the  oral  cavity  (Fig.  6)  is  formed  by  the 
palate,  the  anterior  portion  of  which  is  surrounded  by 
teeth  and  called  the  hard  palate  on  account  of  its  osseous 
base  while  the  posterior  or  muscular  part  is  called  the 
soft  palate. 

On  palpation  the  palate  feels  as  if  a  thin  mucosa  were 
stretched  directly  over  the  bony  plate  of  the  hard  palate. 
This,  however,  is  not  true  as  a  thick  cushion  of  trabecule 
and  laminte  filled  with  flat  lobules  and  acinus  glands  lie 
between  the  mucous  membrane  and  the  periosteum.  This 
cushion  is  thickest  between  the  true  palate  and  the 
alveolar  process  and  gives  the  rounded  form  to  the 
palatine  arches.  The  palatine  arch  is  subject  to  many 
variations  in  different  individuals,  it  may  be  perfectly 
flat,  or  that  of  a  gothic  vault,  or  of  the   varying   forms 


THE  ORAL  CAVITY. 


35 


between  these  tAvo.  The  pathology  of  narrow  and  high 
pahites  wil]  be  discussed  under  the  anomalies  of  the  teeth. 
Back  of  the  middle  incisors  on  the  hard  j^alate  a  pear 
shaped  eminence  is  found  which  is  known  as  the  papilla 
of  the  palate  and  from  ^vhich  a  linear  ridge  or  raphe 
extends  backwards.       Latterly  this  raphe  is  joined  by 


Fig.  6.— Roof  of  the  oral  cavity,     a.  Hard  palate,     b.  Soft  palate. 
d.  The  palatine  papilla. 


c.  Raphe. 


little  ridges  which  run  obliquely  to  the  dental  arch  and 
which  are  called  plme  palafince,  or  folds  of  the  palate. 
These  eminences  are  all  richly  sup|)Hed  with  tactile 
nerves,  which  easily  explains  why  people  wearing  artificial 
teeth  lose  some  of  the  enjoyment  of  tasting  their  food. 
The  papillae  which  are  everywhere  present  in  the  oral 


36 


ANATOMY. 


FIGURE    8. 
The  Vessels  and  Nerves  of  tlie  Hard  Palate. 

a.  The  greater  palatine  artery  with  the  greater  palatine  nerve.  6.  Th-e 
incisor  canal  through  which  the  greater  palatine  artery  anastomoses  with  the 
terminal  branch  of  the  splienopalatine  artery.  The  nasopalatine  uerve 
reaches  the  hard  palate  through  this  canal. 

mucous  membrane  are  taller  and  greater  in  number  in 
the  anterior  part  of  the  mouth  than  near  the  soft  palate. 
The  epithelium  is  a  many-layered  pavement  epithelium 
in  which  the  stratum  corneum  is  missing.  The  super- 
ficial layers  have  not  become  cornified  like  those  of  the 
skin  but  on  the  contrary  the  nuclei  are  plainly  visible. 
The  tissue  lying  between  the  mucosa  and  periosteum  is 
not  of  the  same  nature  everywhere;  the  acinous  glands 
are  more  numerous  in  the  posterior  part  and  especially  in 
the  tissue,  mentioned  above,  which  lies  between  the  hard 
palate  and  the  alveolar  process.      The  palatine  arch  is 


Fig.  7.— a  senile  superior  maxilla  with  perforations  of  the  palatine  plate. 

composed,  aside  from  the  cushion-tissue  which  lies  between 
the  mucosa  and  the  periosteum,  of  dense  bands  of  con- 
nective-tissue which  are  closely  interwoven  with  each 
other  and  intergrown  with  the  niucosa  and  periosteum. 


Fig.  8. 


THE  ORAL  CAVITY.  37 

In  old  age  and  through  the  loss  of  teeth  the  alveolar 
process  undergoes  absorption  and  the  palate  loses  its 
vault.  This  absorption  causes  the  bony  substance  to 
wear  away  so  that  in  extreme  cases  the  nose  is  separated 
from  the  oral  cavity  only  by  soft  tissue,  as  may  be  seen 
in  the  macerated  preparation  in  Fig.  7. 

The  arteries  which  supply  the  hard  palate  pierce  that 
bone  to  the  posterior  and  to  the  medial  sides  of  the  third 
molar  teeth  through  the  pterygopalatine  foramen.  This 
vessel,  spreading  into  many  branches,  lies  directly  upon 
the  bone  and  runs  forward  in  a  direction  parallel  to  the 
tooth  row  (Fig,  8).  This  is  the  greater  jxdatine  artery, 
which,  as  the  largest  branch  of  the  pterygopalatine  artery 
comes  from  the  internal  maxillary  artery.  The  two 
former  arteries  unite  by  means  of  their  smaller  branches 
in  the  neighborhood  of  the  incisor  teeth  where  a  small 
subdivision  passes  into  the  incisor  canal  to  anastomose 
with  the  sphenopalatine  artery. 

The  nerve  supplij  is  derived  from  the  superior  maxillary 
branch  of  the  trigeminal  nerve  and  from  the  nasal  or 
sphenopalatine  ganglion.  The  most  important  is  the 
greater  palatine  nerve  which  leaves  the  pterygopalatine 
foramen  with  the  greater  palatine  artery,  the  width  of 
which  is  about  equal  to  that  of  the  nerve.  This  nerve 
midergoes  anastomosis  in  the  foramen  incisivum  with  the 
nasopalatine  nerve  which  passing  through  the  spheno- 
palatine foramen  runs  forward  along  the  nasal  septum. 

The  soft  palate  begins  about  a  finger  breadth  back  of 
a  line  connecting  the  incisor  teeth  of  tlie  two  jaws.  As  it 
is  composed  of  muscle  tissue  its  form  changes  constantly 
during  observation  ;  it  rises  and  falls  alternately.  The 
uvula  is  suspended  from  above  into  tlie  isthmus  of  the 
fauces  where  its  presence  narrows  the  size  of  this  open- 
ing. The  palatine  arches  spread  out  on  either  side  and 
form  a  space  in  which  the  tonsils  rest.  The  posterior 
palatine  arch  is  the  arcus  palatopharyngeus  and  the  anterior 
is  the  areas  palatoglossus. 

The  floor  of  the  mouth  (Fig.  9)  is  formed  by  the  tongue 
and  the  sublingual  tissue  which  stretches  between  the  rami 


38 


ANATOMY. 


FIGURE   lo. 

The  Superior  Maxilla. 

a.  Alveolar  process,  b.  Zygomatic  process,  c.  Frontal  process,  d.  Alveolar 
eminences,  e.  .interior  nasal  spine.  /.  Canine  fossa,  g.  Infraorbital  foramen. 
h.  Maxillary  tubercleand  the  alveolar  foramen(not  plainly  shown  here)through 
which  the  blood-vessels  and  nerves  pass  to  supply  the  niolar  teeth. 

of  the  inferior  maxilla.  These  structures  are  united  with 
each  other  by  the  frenum  of  the  tongue.  This  frenum  is 
sometimes  so  taut  in  children  as  to  interfere  with  suck- 


FiG.  9.— Floor  of  the  mouth  :  a,  sublingual  gland;  b,  frenum  of  the  tongue  ; 
c,  salivary  caruncle. 

ling ;  in  such  cases  it  is  cut  with  a  pair  of  scissors.  In 
some  abnormal  cases  the  frenum  may  extend  to  the  two 
lower  incisor  teeth  adding,  later  in  life,  to  the  difficulty  in 
using  artificial  teeth.  This  may  be  overcome  in  a  measure, 
however,  by  cutting  suitable  notches  in  the  lower  border 
of  the  plate  to  accommodate  the  frenum. 


Fig.  10. 


THE  ORAL  CAVITY.  39 

Of  the  two  laterally  placed  eminences  between  the 
tongue  and  the  ramus  of  the  jaw,  \\q  will  only  consider 
the  one  formed  by  the  sublingual  gland  with  its  covering 
of  mucous  membrane.  This  gland  rests  below  directly 
upon  the  mylohyoid  muscle  which  separates  it  to  a  great 
extent  from  the  submaxillary  gland.  Internally  it  rests 
upon  the  geniohyoglossus  muscle.  The  excretory  ducts 
of  this  small  gland  open  into  the  mouth  (8-12  in  number) 
in  the  above  mentioned  eminence  as  the  duds  of  Bivinus. 
Aside  from  these  another  larger  excretory  duct,  the  duct 
of  Bartholin,  enters  the  mouth  through  a  pea  sized  emi- 
nence, the  salivary  caruncle,  which  is  situated  under  tlie 
tongue  at  the  back  end  of  the  frenum.  The  excretory 
duct  of  the  submaxillary  gland,  the  duct  of  Mliarton, 
usually  enters  the  mouth  through  the  same  orifice.  The 
submaxillary  gland  may  be  felt  (but  only  when  swollen) 
partly  below  and  in  front  of  the  submaxillary  angle.  It 
lies  in  a  triangle  whicli  is  formed  by  the  edge  of  the  jaw 
and  the  two  bellies  of  the  digastric  muscle.  A  small 
group  of  lymph  glands  are  found  back  of  the  lower  front 
incisors ;  these  are  termed  by  Merkel  {glandula  incisiva) 
the  incisor  glands.  These  glands  all  secrete  reflex ly 
even  when  the  muscles  of  mastication  are  only  slightly 
active.  This  accounts  for  tlie  flooding  of  the  mouth  in 
operations  on  the  floor  of  the  oral  cavity. 

The  tongue  is  attached  only  at  its  posterior  end  wliile 
its  tip  is  freely  movable.  Its  color  is  rather  grayish  in 
comparison  with  the  bright  red  of  the  rest  of  the  oral 
mucosa.  This  shade  is  due  to  a  deposit  of  flat  epithelial 
cells.  The  dentist  has  an  opportunity  to  observe  the 
appearance  of  his  patient's  tongue  daily  and  althougli  a 
liny;ual  coating-  is  no  lono-er  considered  of  as  s^reat  sio-nifi- 
canoe  as  formerly,  yet,  its  condition  in  association  with 
other  symptoms  is  often  of  considerable  diagnostic  value. 
The  coating  of  the  tongue  usually  represents  an  increased 
]>roliferation  of  the  epithelium  which  gives  the  tongue  a 
rough  grayish  appearance.  This  phenomenon  is  explained 
by  Sahli  in  the  trophic  change  of  the  lingual  mucous 
membrane  brought  about  by  disturbances  in  the  alimentary 


40  ANATOMY. 

system.  For  this  reason  a  coated  tongue  is  an  important 
diagnostic  sign  in  dyspepsia.  It  occurs  in  fever  and  in 
other  conditions  accompanied  by  anorexia  and  only  excep- 
tionally does  it  occur  in  good  health  (in  the  writer's 
experience  only  on  the  tongues  of  smokers).  Acute  and 
chronic  gastric  catarrh  is  nearly  always  accompanied  by 
a  coated  tongue. 

When  the  salivary  secretions  are  restricted  as  in  the 
severe  febrile  affections,  the  thickened  mucosa  becomes 
dry,  fissured  and  encrusted,  and  if  hemorrhage  exists,  it  is 
discolored  brown  or  black.  This  picture  of  a  fuliginous 
coated  tongue,  with  which  we  are  well  acquainted,  always 
portends  a  severe  constitutional  disturbance. 

If  fresh  and  scarred  teeth  wounds  are  seen  on  the 
tongue,  which  are  not  traceable  to  a  rough  tooth,  inquiries 
should  be  made  as  to  the  occurrence  of  epileptiform  or 
genuine  epileptic  attacks.  If  the  patient  is  subject  to 
such  convulsive  seizures  and  no  tooth  marks  exists  on  the 
tongue,  hysteria  or  feigning  (malingering)  may  be  sus- 
pected. 

The  arteries  of  the  floor  of  the  mouth,  to  be  especially 
considered,  are  branches  of  the  lingual  artery  which  is  a 
division  of  the  external  carotid.  This  main  branch,  the 
ranine  artery,  runs  superficially  along  the  middle  of  the 
tongue  to  its  tip.  As  this  vessel  is  of  considerable  size 
large  hemorrhages  may  follow  injuries  to  the  tongue,  an 
accident  which  must  not  be  considered  impossible  in 
dental  procedures.  The  dorsal  artery  of  the  tongue  and 
the  sublingual  artery  being  small  branches  are  only 
incidentally  mentioned  in  passing. 

Of  the  nerves  the  hypoglossal,  the  third  branch  of  the 
trigeminal  (from  which  the  lingual  is  derived)  and  the 
glosso-pharyngeal  are  to  be  considered.  The  hypoglossal 
lies  to  one  side  and  underneath  the  submaxillary  gland 
and  sends  its  branches  to  the  musculature  of  the  tongue  of 
which  it  is  the  motor  nerve.  The  tractile  sense  is  sup- 
plied by  the  lingual  nerve,  a  terminal  branch  of  the  third 
division  of  the  trigeminus,  which  through  union  with  the 
chorda    tympani    receives  both   secretory  and  gustatory 


THE  UPPER  JAW  (iMAXILLA).  41 

stimuli  from  the  facialis.  As  is  known  the  facial  nerve 
is  in  reality  a  motor  nerve ;  and  therefore  the  gustatory 
fibres  of  the  chorda  tympani  are  probably  received  from 
the  glosso-pharyngeus,  through  the  minor  superficial 
petrosal  nerve,  or  through  the  anastomosis  of  Jacobson 
from  which  fibres  are  conveyed  to  the  otic  ganglion  and 
from  there  through  the  chorda  tympani  to  the  lingualis. 
The  tongue  fibres  of  the  glosso-pharyngeal  nerve  also 
serve  in  a  lesser  degree  to  carry  impulses  for  the  sense 
of  taste. 


THE  UPPER  JAW  (MAXILLA). 

The  superior  maxilla  is  the  largest  bone  of  the  face. 
It  helps  to  form  the  roof  of  the  oral  cavity,  and  partly  forms 
the  lateral  walls  of  the  nose  and  the  floor  of  the  orbit.  It 
consists  (Fig.  13)  of  a  body  (corpus)  and  four  processes. 

The  lateral  process  is  called  the  zygoma  because  it  con- 
nects with  the  malar  bone.  The  -palatine  p}'ocess  extends 
in  a  medial  direction  and  constitutes  with  its  opposite 
fellow  the  largest  part  of  the  hard  palate.  The  lower 
border  of  the  maxilla,  in  which  the  teeth  are  inserted,  is 
the  alveolar  process.  Above  and  in  front  lies  the  frontal 
process  which  joins  the  nasal,  frontal  and  lachrymal  bones. 

The  body  of  the  upper  jaw  is  not  a  solid  bony  mass 
but,  on  the  contrary,  contains  a  hollow  space,  the  maxillary 
sinus  (antrum  highmori).  This  cavity  is  connected  with 
the  nose  by  an  aperture  in  the  inner  wall  called  the 
maxillary  hiatus  (ostium  maxillare).  On  the  anterior  or 
facial  surface  of  the  alveolar  process  a  number  of  emi- 
nences exist  which  correspond  to  the  teeth  and  are  known 
as  the  alveolar  arches  (  juga  alveolaria)  (Fig.  10,  d). 
Little  depressions  are  noticed  between  these  protube- 
rances, one  of  which  existing  in  front  of  the  well 
developed  root  of  the  cuspid  or  so-called  canine  tooth  is 
called  the  incisive  fossa  ( fossa  incisiva ).  The  shallow 
depression  (canine  fossa)  which  lies  between  the  eminence 
formed  by  the  canine  tooth  and  the  base  of  the  zygomatic 
process  gives  origin  to  the  canine  muscle. 


42  ANATOiVY. 

FIGURE   II. 

Superior  maxilla  with  the  antrum  opened. 

To  show  the  relationship  between  the  latter  and  the  roots  of  the  teeth,  o. 
Maxillary  sinus,  b.  Maxillary  process  of  the  inferior  turbinated  bone.  c.  Per- 
pendicular portion  of  the  palatine  bone.  d.  Ethmoidal  process  of  the  inferior 
turbinated  bone.  e.  Unciform  process.  /.  Orbital  surface,  g.  Fossa  for  the 
lachrymal  sac.  h.  Sphenopalatine  foramen,  i.  Pterygopaiatine  fossa,  k. 
Third  molar  tooth  erupting  posteriorly. 

The  infraorbital  for  ainen  lies  a  few  millimeters  beneath 
the  orbital  ridge,  approximately  over  the  root  of  the  first 
bicuspid  tooth.  This  foramen  contains  the  infraorbital 
nerve,  the  branches  of  which  enter  the  bony  structure  to 
suj^ply  the  teeth. 

A  rough  eminence  on  that  portion  of  the  maxilla  which 
lies  back  of  the  zygomatic  process  is  called  the  maxiUary 
tuberosity.  In  front  of  the  zygomatic  process  the  anterior 
or  facial  surface  ends  in  a  pear-shaped  notch  marking  the 
beginning  of  the  nasal  cavity,  which  is  called  the  pyriform 
aperture. 

The  orbital  surface  (superficies  orbitalis)  is  smooth  and 
slopes  gradually  out\^'ard.  Its  regularity  is  only  inter- 
rupted by  a  groove,  the  infraorbital  sulcus,  whicli  passing 
forward  into  a  similarly  named  canal  terminates  in  the 
above  described  infraorbital  foramen.  Another  small 
depression,  to  be  mentioned,  lies  in  the  inner  and  anterior 
part  of  the  orbital  surface  and  gives  origin  to  the  internal 
oblique  muscle. 

On  the  inner  or  nasal  surface  of  the  superior  maxilla, 
near  the  base  of  the  frontal  process,  is  the  crest  for  artic- 
ulation with  the  inferior  turbinated  bone.  The  foramen 
which  connects  the  antrum  of  Highmore  with  the  middle 
meatus  of  the  nose  lies  in  the  upper  portion  of  the  nasal 
surface  and  is  partly  covered  by  a  curved  cartilaginous 
plate  called  the  lamina  laorymalis.  The  ptery go-palatine 
groove  wdiich  helps  the  palate  bone  to  form  the  pterygo- 
palatine canal  runs  obliquely  forward  and  downward,  its 
lower  rough  edge  connects  Avith  the  palate  bone.  Of  the 
various  processes  of  the  superior  maxilla,  the  frontal  and 
zygomatic  interest  us  less  than  the  palatine  and  the 
alveolar. 


Fig.  11. 


THE   UPPER  JAW  {MAXILLA). 


43 


The  palatine  process  extends  as  a  quadrangular  shaped 
bony  plate  in  a  horizontal  direction  from  the  lower  medial 
surface  of  the  superior  maxilla.  The  two  palatine  pro- 
cesses meet  in  the  middle  line  and  form  three-fourths  of 
the  hard  palate ;  the  other  quarter  being  formed  by  the 
horizontal  portion  of  the  palate  bone.  The  lower  or  oral 
surface  is  arched,  rough  and  grooved  for  the  transmission 
of  blood-vessels  and  nerves.      Posteriorly  the  serrated 


Fig.  12. — Horizontal  seotions  through  the  alveolar  process  of  tlie  superior 
maxilla,  a.  Central  incisors,  b.  Lateral  incisors,  c.  Cuspid  teeth.  (/.  First 
bicuspid,  c.  Second  bicuspid.  /.  First  molar,  g.  Second  molar,  h.  Third  molar 
tooth. 

edged  palatine  process  of  the  superior  maxilla  connects 
with  the  horizontal  plate  of  the  palate  bone,  while  in  the 
middle  line  the  upper  surface  bears  a  crest  for  union  with 
the  vomer.  A  canal  pierces  the  plate  of  the  palate  bone 
near  the  incisor  teeth  (cavalis  incishms)  and  enters  the 
oral  cavity  as  thefuramen  incisivum. 

The  lower  border  of  the  alveolar  process  of  the  superior 


44  ANATOMY. 

FIGURE  13. 

Eontgen  ray  photograph  of  the  superior  maxilla  and  its  neighboring  structures. 

maxilla  contains  the  alveoli  in  which  the  roots  of  the 
teeth  are  inserted.  It  is  of  the  greatest  import  both  for 
extraction  and  treatment  of  the  roots  to  possess  an  exact 
knowledge  of  the  topographic  relationship  of  these  alveoli. 
This  can  be  obtained  in  no  better  way  than  by  making 
horizontal  sections  similar  to  those  shown  in  figure  12. 
For  a  description  I  will  refer  the  reader  to  the  text 
accompanying  the  illustrations. 

A  Rdntgen  ray  photograph  of  the  normal  superior 
maxilla  and  its  neighboring  structures  is  reproduced  in 
Fig.  13,  for  not  until  the  reader  is  acquainted  with  the 
appearance  of  such  a  picture  is  it  possible  to  recognize 
pathologic  conditions  as  shown  in  a  skiagram. 

THE  INFERIOR  MAXILLA. 

(Mandibula,  Plate  L). 

The  inferior  maxilla  is  not  attached  to  the  upper  jaw 
through  bony  union  but  is  connected  with  it  by  an  artic- 
ulating joint.  This  is  the  heaviest  and  strongest  of  all  the 
bones  of  the  head,  and  is  divided  into  the  body  or  hori- 
zontal portion,  and  two  rami  or  ascending  branches,  and 
the  alveolar  process. 

In  old  age  atrophy  of  this  process  and  flattening  of  the 
angle  of  the  bone  accounts  for  the  apparent  protrusion  of 
the  lower  jaw.  The  outer  walls  of  the  alveoli  are  gener- 
ally thinner  than  the  inner,  for  which  reason  in  extraction 
of  the  lower  teeth,  the  force  is  principally  directed  out- 
ward. The  jaw  bone  is  thickened  in  the  region  of  the 
second  and  third  molar  teeth  through  the  oblique  line 
which  lies  on  the  buccal  surface.  This  is  especially 
noticeable  when  the  roots  are  removed,  yet  sometimes  it 
cannot  be  detected  until  resection  forceps  are  applied 
(Fig.  14)..  A  cross  section  of  the  body  of  the  jaw,  as 
presented  in  Fig.  14,  shows  an  outer  hard  compact  mass 
surrounding    an   inner    spongoid    substance   with   wide 


Fig.   U. 


^ 


m 


THE  INFERIOR  MAXILLA. 


45 


meshes,  the  trabeculfe  of  which  form  the  mandibular  canal 
and  assist  in  supporting  it.  The  medullary  space  extends 
close  to  the  tips  of  the  roots  and  surround  it  on  both  the 
buccal  and  lingual  sides.  This  explains  the  rapid  exten- 
sion of  affections  of  the  periodontium  to  the  jaw  bone, 
and  also  accounts  for  the  relatively  rapid  absorption  from 
the  apical  foramen  of  soluble  poisons  which  are  placed  in 
the  tooth  cavity.  Severe  intoxications  of 
a  greater  or  less  degree  may  thus  develop 
especially  in  those  who  are  subject  to  idio- 
syncratic tendencies.  Figs.  15  and  16 
illustrate  the  topographic  relationshi])  of 
the  alveolar  process,  in  which  the  position 
and  direction  of  the  roots  are  well  shown 
as  well  as  the  alveolar  and  spongy  cavities. 

The  ascending  ramus  is  thinner  and 
flatter  than  the  body  of  the  jaw.  At  its 
upper  end  it  divides  into  two  processes 
the  coronoid  process  on  which  the  tem- 
poral muscles  are  inserted,  and  a  posterior 
process,  the  co)idyloid  py^ocess  which  artic- 
ulates with  the  cranium  by  means  of  a 
transversely  placed  condyle. 

The  joint  of  the  inferior  maxilla  bone  is  most  interest- 
ing. It  is  like  a  double  joint  in  which,  however,  the  artic- 
ulations of  the  two  sides  must  act  simultaneously  since 
they  are  incapable  of  independent  movements.  An  emi- 
nence in  front  of  the  glenoid  cavity  is  called  the  articular 
tubercle.  The  glenoid  cavity  contains  an  iuterarticular 
cartilage,  and  when  the  mouth  is  opened  the  condyle  of 
the  inferior  maxilla  glides  forward  with  its  iuterarticular 
cartilage  over  this  tubercle.  In  as  much  as  the  inferior 
maxilla  possesses  two  articulations  ankylosis  may  fail  to 
deveh^p  even  if  both  joints  are  considerably  diseased,  jiro- 
vided  that  one  joint  is  less  affected  tlian  the  other. 

Backward  luxation  of  the  inferior  maxilla  is  prevented 
by  the  tympanic  })late  of  the  temporal  bone,  and  lateral 
displacement  by  the  sj)ine  of  sphenoid  bone.  The  only 
dislocation  possible  is  in  the  forward  direction  which  is 


Fig. 14. —Cross  sec- 
tion of  the  ascend- 
ing ramus  of  the 
inferior  maxiUa. 
(/.  Buccal,  b.  Lin- 
fiual.  c.  Mandibular 
canal. 


46 


ANATOMY. 


PLATE   I. 

Lower  jaw  of  an  adult :  The  upper  picture  shows  the  buccal,  and  the 
lower,  the  lingual  side  :  a,  mental  foramen  ;  b,  mental  protuberance  ;  c, 
alveolar  eminence  ;  d,  oblique  line  ;  e,  coronoid  process  ;  /,  condyloid  pro- 
cess ;  g,  mandibular  foramen  ;  h,  digastric  fossa  ;  ?',  mental  spine  ;  j,  sub- 
lingual fossa ;  Ic,  mylohyoid  line  ;  I,  lingual ;  m,  submaxillary  fossa. 


FIGURE   15. 

Horizontal  sections  through  the  alveolar  process  of  the  lower  jaw: 

a,  central  incisors ;  6,  lateral  incisors;  c,  cuspid  teeth  ;  rf,  first  bicuspid  ; 
e,  second  bicuspid ;  /,  first  molar ;  g,  second  molar ;  h,  third  molar. 

comparatively  easy  since  the  physiological  forward  move- 
ment of  the  condyle  on  the  articular  tubercle  is  strictly 
speaking  already  a  subluxation,  and  only  a  slight  violence 
is  then  necessary  to  force  it  over  that  eminence  in  the 
infratemporal  fossa.  The  condyle  once  displaced  into 
this  position  requires  considerable  strength  to  reduce  it 


Fig.  16.— Lower  jaw,  from  which  the  buccal  plate  has  been  removed  in 
order  to  show  the  distribution  of  the  spongiosa  and  the  course  of  the  man- 
dibular canal. 

on  account  of  the  contraction  of  the  strong  muscles  of 
mastication.  The  lower  jaw  is  habitually  displaced  when 
the  accessory  ligaments  and  the  muscles  of  mastication 


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Fig.  15. 


THE  INFERIOR  MAXILLA. 


Al 


are  relaxed,  otherwise  this  bone  is  dislocated  only  through 
forcible  opening  of  the  mouth  through  a  fall,  blow,  etc. 

In  old  age  when  all  the  teeth  have  disappeared  the 
alveolar  process  of  the  inferior  maxilla  becomes  absorbed 
and  only  the  body  together  with  a  more  or  less  serrated, 
sharp  bony  ridge  remains,  the  latter  indicating  the  former 


Fiii.  17.— A  senile  lower  jaw  with  atrophy  of  the  alveolar  process. 


position  of  the  alveolar  ]irocess.  Under  such  circum- 
stances an  artificial  denture  is  retained  with  difficulty. 
The  Rontgen  ray  picture  in  Fig.  IS,  like  that  of  the  upper 
jaw,  gives  the  normal  radiographic  appearance  of  the 
inferior  maxilla. 


48 


ANATOMY. 


THE  BLOOD-VESSELS  AND  NERVES  OF  THE  TEETH. 

The  internal  maxillary  artery,  through  its  branches, 
supplies  blood  to  all  of  the  teeth  and  their  neighboring 
structures.  The  lower  jaw  gets  its  blood  supply  from 
the  inferior  dental  artery,  which  runs  along  the  lingual 
surface  of  the  ascending  ramus,  passes  through  the  mandi- 
bular foramen  into  the  canal  of  the  same  name  and  leaves 
the  bone  by  the  mental  foramen,  in  the  region  of  the  bicus- 
pids, on  the  buccal  aspect.  From  the  mandibular  canal 
this  artery  sends  branches  to  the  teeth,  called  the  dental 


Fig.  is.— a  Rontgeii  ray  photograph  of  the  lower  jaw.    a,  mental  foramen. 

rami,  and  also  branches  between  the  teeth,  known  as 
interalveolar  rami.  The  latter  subdivide  into  the  r/ingival 
perforating  branches  which  supply  the  gums  and  the  aire- 
olar  perforating  branches  which  sup]jly  the  alveoli  and  the 
periosteum.  A  rich  anastomosis  exists  between  the  dental 
and  the  interalveolar  rami,  an  arrangement  Mhich  accounts 
for  the  transmission  of  circulatory  disturbances  from  one 


BLOOD-VESSELS  AND  NERVES  OF  THE  TEETH.    49 

part  to  another.  The  blood-vessels  of  the  upper  jaw  are 
subdivided  iuto  terminal  branches  like  those  described  for 
the  lower  jaw  and  therefore  need  not  be  referred  to  here. 

The  alveolar  process  of  the  upper  jaw  is  supplied  by 
the  infraorbital  artery  which  arises  from  the  third  division 
of  the  internal  maxillary  artery.  The  superior  posterior 
alveolar  artery  arises  either  directly  from  the  latter  or 
from  the  infraorbital.  When  it  arises  from  the  infra- 
orbital, it  is  subdivided  in  the  region  of  the  pterygo- 
palatine fossa  ^vhere  it  passes  through  the  inferior  orbital 
fissure  into  the  orbits.  Near  its  origin  it  divides  into 
minute  ramifications  (superior  j^osterior  alveolar  arteries) 
which  at  the  maxillary  tubercle  enter  the  alveolar  canals 
through  the  alveolar  foramina  and  pass  forward  into  the 
maxillary  sinus.  From  here  these  small  arteries  reach 
the  upper  molars  and  their  surrounding  structures.  During 
tlie  passage  of  the  infraorbital  artery  through  the  infra- 
orbital canal  it  sends  off  abundant  anastomosing  branches, 
the  anterior  superior  alveolar  arteries  which  enclosed  in 
complete  and  semi-complete  canals,  supply  the  bicuspid, 
the  cuspid,  and  the  incisor  teeth. 

As  the  veins  correspond  to  the  arteries  a  description  of 
tliem  will  be  omitted.  Attention,  however,  is  called  to 
the  beautiful  plexus  formed  by  the  mandibular  vein  which 
lies  in  the  inferior  dental  canal  (Plate  2).  All  maxillary 
veins  empty  into  the  internal  pteri/gopalatine  plexus  which. 
is  situated  in  the  pterygo-maxillary  fossa.  This  plexus 
sends  its  blood  into  the  external  jugular  vein. 

The  trigeminal,  the  fifth  cranial  nerve,  supplies  the 
teeth  with  fibres  for  sensation.  As  is  well  known,  three 
branches  issue  from  the  Gasserian  ganglion  :  (1)  Ophthal- 
mic, (2)  Superior  maxillary,  and  (3)  Inferior  maxillary. 
The  superior  maxillary  nerve  passes  out  through  the 
foramen  rotund um.  Its  terminal  branches,  the  infra- 
orbital nerve,  runs  practically  the  same  course  as  the 
similarly  named  artery.  This  nerve  supplies  the  molar 
teeth  with  its  posterior  alveolar  branches,  the  bicuspid 
teeth  through  the  median  alveolar  nerves  and  the  cuspid 
and  incisor  teeth  through  the  anterior  alveolar  nerves. 


50  ANATOMY. 

PLATE  2. 

The  blood-vessels  and  nerves  of  the  teeth.  This  semi-schematic 
preparatiou  shows,  through  partial  removal  of  the  buccal  plates,  the 
distribution  of  the  blood-vessels  and  nerves  within  the  spongy  portion  of 
the  bone.  By  grinding  the  roots  of  the  teeth,  their  most  important  con- 
tents (arteries,  veins  and  nerves)  are  shown. 

The  posterior  branches  which  spring  from  the  infraorbital 
nerve  before  its  entrance  into  the  orbit,  enter  the  bone  at 
the  maxillary  tuberosity  and  unite  through  loops  with  the 
anterior  branches.  Small  branches  called  the  "  medii  " 
run  from  these  loops  [arcus  sujjramaxlllm-is)  to  the  bicuspid 
teeth.  Just  before  issuing  from  the  infraorbital  canal, 
the  infraorbital  nerve  gives  rise  to  the  origin  of  the  anterior 
alveolar  nerves  ;  these  by  fusion  with  one  another  and  with 
the  offshoots  from  the  supramaxillary  arc  form  a  ganglion 
(supramaxillary)  which  lies  over  the  root  of  the  cuspid 
teeth.  Small  branches  from  this  ganglion  supply  the 
cuspid  and  incisor  teeth,  (According  to  J.  Scheff  the 
term  "  ganglion "  is  not  absolutely  correct  as  typical 
ganglion  cells  are  not  present). 

The  inferior  maxillary  nerve  leaves  the  base  of  the 
skull  through  the  foramen  ovale.  Its  terminal  branch, 
the  mandibular  nerve,  passes  into  the  inferior  dental  fora- 
men in  which,  covered  by  the  lingual  nerve,  it  disappears 
with  the  lingual  artery  and  vein.  Before  it  enters  the 
lower  jaw  it  furnishes  the  mylohyoid  muscle  with  motor 
fibres.  It  leaves  the  inferior  maxilla  through  the  mental 
foramen  where  it  supplies  the  skin  of  the  lower  lip  and 
the  chin  with  fibres  for  sensation.  Exactly  like  the 
arteries,  this  nerve  during  its  course  through  the  inferior 
dental  canal  gives  off  dental  rami  for  the  tooth  pulp  and 
interalveolar  ramifications  for  the  bony  septum. 


CORROSION  ANATOMY  OF  THE  TEETH. 


51 


CORROSION  ANATOMY  OF  THE  TEETH  AND 
THE  PNEUMATIC  CAVITIES  OF  THE  FACE, 

CORROSION  ANATOMY  OF  THE  TEETH. 

The  technic  for  the  corrosion  of  the  teeth  consists  at 
first  in  thoroughly  macerating  the  teeth  for  three  ■weeks 
at  30°  C.  The  roots  are  then  "wrapped  in  blotting  paper 
and  set  upright  in  a  moderately  thick  layer  of  plaster  of 
Paris.  A  hole  is  drilled  through  to  the  pulp,  in  which  a 
stiff  paper  funnel  about  1  decimeter  long  is  inserted  and 


Fig.  19.— Metallic  casts  of  the  teeth  of  the  upper  and  lower  jaws.    The 
tooth  belonging  to  each  cast  is  presented  as  being  transparent. 

fastened  with  gelatine.  After  the  plaster  of  Paris  and 
gelatine  are  thoroughly  dried  by  heating,  the  whole  is 
carefully  heated  to  such  a  degree  that  -when  a  small  bit 
of  Wood's  metal  is  placed  in  the  funnel  it  begins  to  melt. 
This  metal  is  added  until  the  column  of  metal  has  reached 


52 


ANATOMY. 


PLATE   3. 

Metallic  cast  of  the  combined  pneumatic  cavities  of  the  face,    a, 

inferior  nasal  fossa;  b,  middle  nasal  fossa;  c,  superior  nasal  fossa;  d, 
sphenoidal  sinus  ;  e,  internal  carotid  artery  ;  /,  sheath  of  the  optic  nerve; 
g,  antrum  of  Highmore ;  h,  iufundibulum. ;  i,  nasolacrymal  canal ;  j, 
ethmoidal  cells  ;  h,  frontal  sinus. 

FIGURE  22. 

Metallic  cast  of  the  maxillary  sinus,  showing  the  relationship  of 
the  teeth  to  the  antrum  Fig.  22.  a,  cast  of  the  pulp  cavity  of  a  young, 
and  b,  of  an  old  individual. 

such  a  height  as  to  furnish  sufficient  pressure  to  force  the 
metal  into  the  smallest  canals. 

After  cooling,  place  the  metal  filled  tooth  in  a  solution 
of  20  per  cent,  liquor  potassse  at  a  temperature  of  from 
40-50°  C,  for  from  three  to  four  weeks.  In  this  manner 
the  tooth  substance  becomes  softened  and  the  metal  cast 


v..:^ 


Fig.  20. 


which  occupies  the  pulp  cavity  may  be  easily  removed. 
The  accompanying  figures  show  preparations  obtained  in 
this  manner.     In  order  to  better  show  the  topographical 


Fig.  22. 


CORROSION  ANATOMY  OF  THE  TEETH.  53 

position  of  the  pulp  cavities  the  contours  of  the  teeth  are 
traced  around  the  casts. 

For  the  conservative  practice  of  dentistry  a  thorough 
knowledge  of  the  pulp  cavity  and  the  root  canals  is 
absolutely  necessary,  and  there  is  probably  no  better 
method  for  showing  their  various  characteristics  than  in 
the  above  manner.  Fig.  19  shows  the  corrosion  of  the 
whole  upper  and  lower  row  of  teeth.  It  is  seen  in  these 
drawings  that  the  metal  cast  assumes  the  form  of  the 
tooth,  only  smaller  in  size,  thus  the  metal  cast  of  the 
cuspid  tooth  is  shovel  shaped,  that  of  the  molar  teeth, 
multicuspidate,  etc.  Equally  as  important,  at  least  froni^ 
a  clinical  point  of  view,  is  the  form  of  the  metal  cast  of 
the  root  canals.  This  shows  a  surprising  and  hithertofore 
unknown  condition,  namely  that  not  rarely  in  certain 
roots  an  anastomotic  canal  system  exists  which  may  be 
demonstrated  by  the  richly  branching  network  in  the 
cast.  The  buccal  and  mesial  roots  of  the 
lower  molars  possess  this  peculiarity  most 
frequently. 

A  tooth  showing  an  anastomotic  canal 
system  especially  well,  is  illustrated  in  Fig. 
20.  It  is  also  noted  from  the  casts  presented 
in  Fig.  19  that  the  volume  of  the  pulp 
cavity  differs  in  the  three  molar  teeth, 
both  in  the  upper  and  lower  jaw.  The  ealtofJuIi^^cS-: 
cast  of  the  pulp  cavity  of  the  iirst  molar  is  ?. !»  ^  young  sub- 

,  11  •  •  •  1      ,1  •         ject ;  6,  m  au  older 

the  smallest  m  comparison  with  the  size  individual. 
of  the  crown  while  the  casts  of  the  other 
molars  increase  in  size  consecutively  from  the  second  to 
third.  This  is  explained  by  the  fact  that  the  first  molar 
is  the  oldest,  and,  as  is  known,  the  pulp  cavity  in  the 
course  of  time  becomes  smaller  through  concentric  growth 
of  the  solid  portion  of  the  tooth.  This  concentric  growth 
is  not  the  same  In  all  directions,  but  as  Szabo. teaches,  In  a 
60  year  old  Individual  It  measures  3  mm.  In  the  length  and 
only  1  mm.  in  width.     This  is  shown  in  Fig.  21. 


54  ANATOMY. 

CORROSION  ANATOMY  OF  THE  PNEUMATIC  CAVITIES 
OF  THE  FACE. 

In  order  to  obtain  models  of  the  facial  cavities  it  is 
advisable  to  treat  the  head  with  alcohol  for  a  long  time, 
and  only  when  it  has  become  thoroughly  dehydrated, 
should  it  be  impregnated  with  turpentine,  according  to 
the  method  of  Semper-Riehm.  When  the  parts  are 
thoroughly  dried  they  are  placed  in  plaster  of  Paris  and 
Wood's  metal  is  poured  in  through  an  opening  drilled 
through  the  facial  surface.  The  corrosion  then  occurs  as 
in  the  teeth  through  the  action  of  liquor  potassee. 

A  cast  of  the  right  half  of  the  head  of  a  male  adult  is 
presented  in  Plate  3.  A  number  of  other  cavities  than 
those  considered  as  belonging  to  the  face  are  included  in 
this  cast,  such  as  the  sheath  of  the  optic  nerve,  a  con- 
volution of  the  internal  carotid  artery  and  the  nasolacry- 
mal  canal.  The  facial,  the  posterior  and  the  orbital  walls 
of  the  antrum  of  Highmore  are  seen  in  this  illustration. 

The  frontal  sinus  which  was  reached  through  the 
infundibulum  of  the  ethmoid  bone  and  the  short  naso- 
frontal canal  is  seen  above  and  in  front.  The  frontal 
sinus  in  this  figure  is  poorly  developed  in  comparison 
with  other  preparations.  The  outer  aspect  of  eleven 
ethmoidal  cells  which  are  separated  from  one  another  by 
deep  grooves  may  also  be  recognized  in  this  preparation. 
Immediately  behind  these  cells  and  extending  some  dis- 
tance in  a  lateral  direction  is  a  cast  of  sphenoidal  sinus 
which  is  shaped  like  the  body  of  that  bone. 

The  model  taken  as  a  whole  teaches  us  to  recognize 
the  connection  which  exists  between  these  various  hidden 
cavities  and  explains  how  easily  an  affection  of  one  cavity 
can  be  transmitted  to  another.  It  also  shows  us  their 
relations  to  the  teeth,  especially  the  three  molars  which 
because  of  the  danger  of  starting  an  empyema  must  be 
treated  with  special  care.  In  order  to  show  the  close 
relationship  of  the  molar  roots  to  the  antrum,  a  corrosion 
specimen  (Fig.  22)  of  the  skull  has  been  prepared  which 
shows  the  exact  position  of  the  antrum  of  Highmore. 


SPECIAL  ANATOMY  OF  THE  TEETH.  55 

SPECIAL  ANATOMY  OF  THE  TEETH. 

(  Plate   4.  ) 

Man,  who  is  diphyodcut,  develops  two  sets  of  teeth, 
one  which  appears  early  in  life,  the  deciduons  set,  twenty 
in  number,  and  a  subsequent  permanent  set  which  is  com- 
posed of  thirty-two  teeth. 

From  a  topographical-anatomical  standpoint,  each 
tooth  may  be  divided  into  three  distinct  parts  which  are 
sharply  defined  from  one  another.  The  part  which  is 
inserted  in  the  alveolar  process  of  the  jaw  is  termed  the 
root  (radix) ;  the  portion  surrounded  by  the  gum  is  the 
nech  (collum),  and  the  free  part  which  stands  in  the  mouth 
is  the  croicn  (corona).  These  divisions  also  show  histo- 
logical differences.  The  root  is  covered  with  cementum  a 
substance  somewhat  similar  to  bone,  which  gradually 
becomes  thinner  as  the  neck  of  the  tooth  is  approached, 
where  it  forms  a  structureless  sheath  of  paper  thickness. 
The  crown  is  covered  with  the  hardest  of  all  animal  sub- 
stances namely,  the  enamel. 

It  is  very  useful  for  the  sake  of  exact  localization  to 
distinguish  the  followina;  areas  on  each  individual  tooth. 
The  outer  surface  of  the  tooth  which  is  exposed  to  the 
lips  or  cheek  is  called  the  labial  or  buccal  surface,  the 
opposite  surface  wliich  is  exposed  in  the  oral  cavity  to 
tlie  tongue,  is  called  the  linr/ual  or  jjalat'me  surface.  As 
the  teeth  are  arranged  one  after  the  other  in  the  form  of 
a  horse-shoe,  it  is  easy  to  explain  why  the  surface  of  the 
tooth  turned  to  the  middle  or  median  line  of  the  face 
should  be  called  mesial,  and  the  side  turned  away  from 
the  middle  line,  the  distal  surface.  A  mesial  and  distal 
surface  togctlier  form  an  approximal  surface.  At  the  neck 
of  the  tooth  one  speaks  of  a  cervical  or  marginal  localiz- 
ation. The  free  ends  or  edges  of  the  incisor  and  the 
cuspid  teeth  are  called  the  cutting  or  incisal  surfaces, 
while  the  corresponding  parts  of  the  bicuspids  and  molars 
are  called  the  f/rindincj  or  rnasticatinc/  surfaces.  The  roots 
of  the  teeth  are  conical  in  shape,  flattened  laterally,  and 
gradually  taper  to  a  point.     They  fit  tightly  in  the  alveoli 


56  SPECIAL  ANATOMY  OF  THE  TEETH. 

PLATE  4. 

Upper  illustration.    Lateral  view  of  the  permanent  teeth.    Lower 
illustration.     Lateral  view  of  the  milk  or  temporary  teeth. 

and  are  separated  from  the  bone  only  by  a  thin  sheath  of 
connective-tissue,  the  alveolar  periosteum.  The  chief  func- 
tion of  this  membrane  is  to  hold  the  teeth  firmly  in  place 
through  dense  bundles  of  fil)rons  tissue  which  extend 
from  the  alveoli  to  the  cementum  and  the  gums.  The 
teeth  are  inserted  in  the  alveoli  in  this  manner,  in  order 
that  the  pressure  in  masticating  is  not  alone  brought  to 
bear  upon  the  apex  of  the  root,  through  which  the  blood- 
vessels and  nerves  enter  the  tooth,  but  that  it  may  be 
shared  by  the  whole  wall  of  the  alveolus.  Aside  from 
the  foregoing  mentioned  hard  substances,  the  cementum 
and  enamel,  we  must  still  consider  a  third  which  is  the 
most  important  substance  of  all  teeth,  namely,  the  dentin. 
This  material  encloses  the  tooth  pulp  with  its  rich  cellular 
odontoblastic  sheath. 

THE  PERMANENT  TEETH. 

(See  Plate  4.     Upper  Illustration,  and  Figure  23.) 

The  completed   permanent   set  consists  of  thirty-two 
teeth  which  are  arransred  as  follows: 


=32 


The  two  jaws  then  possess  in  all ;  8  incisors  (I)  [cutting 
teeth]  ;  4  cuspids  (C),  8  bicuspids  (B),  and  12  molars  (M). 

The  shape  of  the  teeth  in  the  different  sections  of  the 
jaw  depends  upon  the  duties  they  are  required  to  perform; 
thus  the  front  teeth  which  sever  the  food  form  sharp 
chisels  which  overlap  like  a  pair  of  shears,  while  the 
masticating  teeth  are  supplied  w'ith  broad,  cusped  crowns 
which  crush  the  food. 


M 

B     C     I 

I 

C 

B    M 

3 

2     1     2 

2 

1 

2     3 

3 

2     12 

2 

1 

2     3 

Tab. 


THE  PERMANENT  TEETH. 

Incisors. — The  crowns  of  the  upper  incisors  are  shovex 
or  chisel  shaped.  The  horizontal  edge  is  like  that  of  a 
dull  knife,  which  in  youth  becomes  easily  indented.  These 
indentations  (usually  3),  however,  soon  wear  away  through 
use.  There  are  in  each  of  the  upper  and  lower  jaws  four 
incisors,  that  is  eight  in  all.  In  the  upper  jaw  the  central 
incisors  are  larger  than  the  lateral  while  in  the  lower 
jaw  the  lateral  are  larger  than  the  central  incisors.  The 
labial  surface  is  slightly  convex  and  relatively  smooth 
while  the  lingual  is  concave  and  possesses  a  fold  of 
enamel  which  in  the  laterally  placed  incisors  forms  a  fossa 
known  as  the  foramen  coecum,  an  area  ^\•hich  predisposes 
to  caries.  In  many  mammals,  especially  the  horse,  an 
enamel  shell  which  is  filled  with  ceuientum  exists  on  the 
labial  surface  of  the  incisor  teeth  ;  this  peculiarity  called 
the  "  mark  "  is  a  criterion  of  the  animal's  age. 

In  man  the  mesial  border  joins  the  horizontal  edge  at  a 
sharp  turn  forming  almost  a  right  angle  with  it,  while  the 
distal  edge,  ou  the  contrary,  is  more  rounded.  From  the 
neck  of  the  teeth,  which  is  separated  from  the  crown  by 
a  ring  of  enamel,  a  simple  slender  root  extends  down- 
ward which  is  stronger  in  the  central  than  in  the  lateral 
incisors.  The  roots  of  the  middle  incisors,  on  cross 
section,  are  seen  to  be  round  while  the  lateral  ones  are 
oval  (Fig.  12);  a  condition  Avhich  should  receive  s}x?cial 
attention  in  extraction.  The  pulp  cavity  is  relatively 
spacious  and  its  extension  downward  is  easily  probed. 

The  lower  incisors  stand  vertically  in  the  jaw ;  they 
are  much  smaller  than  the  upper  ones,  and  the  central  are 
even  smaller  than  the  lateral  incisors.  The  roots  are 
closely  pressed  together  on  each  side  and  cannot  be 
removed  through  twisting,  as  can  for  example,  the  central 
upper  incisors. 

Canine  or  Cuspid  Teeth. — The  cuspid  teeth  are 
four  in  number;  two  in  the  upper  and  two  in  the  lower 
jaw.  They  are  strongly  developed,  especially  the  upper 
ones,  which  represent  the  most  powerful  of  the  cutting  set 
of  teeth.  The  crown  shows  a  convexity  of  considerable 
degree  on  the  labial  surface,  while  on  the  lingual  surface 


58  SPECIAL  ANATOMY  OF  THE  TEETH. 

FIGURE  23. 

Permanent  teeth  seen  from  aljoye :  a,  upper,  6,  lower  tooth  row. 
The  upper  set  approaches  an  elliptical,  the  lower  set  a  parabolic  form. 

a  small  tubercle  is  presented  which  resembles  the  lingual 
cusps  of  the  bicuspid  teeth  and  forms  a  connecting  link 
between  the  narrow  incisors  and  the  broad  molars. 

The  labial  edge  of  the  cuspid  tooth  slopes  into  a  sharp 
point.  It  is  easy  to  distinguish  the  right  from  the  left 
tooth  by  the  fact  that  this  point  does  not  lie  in  the  middle 
of  the  tooth  but  rather  to  the  mesial  side,  and  hence  the 
distal  edge  of  this  tip  is  longer  and  steeper  than  the 
mesial  edge.  This  also  holds  true  for  the  lower  and 
somewhat  smaller  teeth.  The  roots  of  the  upper  cuspid 
are  especially  well  developed  and  on  cross  section  are  oval 
shape.  Those  of  the  lower  teeth  are  somewhat  weaker 
and  are  more  flattened  laterally  (Fig.  12).  The  pulp 
cavity  is  spacious  and  more  easily  accessible  than  in  any 
of  the  other  teeth. 

Bicuspids  (Premolars). — Two  bicuspid  teeth  stand 
next  to  the  cuspid  teeth  on  both  sides  of  each  jaw,  and 
accordingly  there  are  altogether  eight  in  number.  They 
are  somcAvhat  weaker  than  the  cuspid  teeth  which  they 
resemble  on  their  labial  aspect.  Through  the  addition 
of  a  short  lingual  cusp  their  bodies  are  increased  in  size 
and  tend  in  this  respect  to  approach  the  molars  in  shape. 

The  upper  bicuspids  possess  two  well  developed  cusps, 
of  which  the  labial  is  somewhat  longer  and  sharper  than 
the  lingual.  The  first  and  second  bicuspids  resemble  each 
other  so  closely  in  regard  to  their  crowns  that  it  is 
difficult  to  distinguish  them  from  one  another.  Although 
the  formation  of  their  roots  varies  considerably,  it  may  be 
accepted  as  a  general  rule  in  distinguishing  between  the 
upper  bicuspids,  that  the  first  has  usually  two  roots,  while 
the  second  bicuspid  has  only  a  single  root  which  is  con- 
siderably flattened  laterally. 

Since'  the  lingual  cusp  of  the  first  lower  bicuspid  is 
simply  formed  by  a  tubercle,  this  tooth  closely  resembles 
the  shape  of  the  cuspid  tooth.  It  usually  possesses  only 
one  root  which  is  very  weak  in  comparison  with  that  of  the 


Fig.  23. 


THE  PERMANENT  TEETH.  59 

cuspid  tooth.  On  cross  section  it  is  oval  in  shape,  and 
shows  longitudinal  grooves  Avhich  run  from  the  mesial  to 
the  distal  surface. 

The  second  lower  bicuspids  are  the  largest  of  the 
bicuspid  group  of  teeth.  Their  crowns  consist  of  one 
strong  labial  and  two  smaller  lingual  cusps,  that  is  three 
cusps  in  all.  This  gives  the  grinding  surface  a  consider- 
able circumference.  Their  roots  are  single,  oval  and 
fairly  strong.  In  the  lower  bicuspids  the  roots  are  set 
vertically  in  the  jaw  and  consist  of  one  piece,  hence  it  is 
nearly  always  easy  to  pass  a  sound  into  the  centrally 
placed  root-canal. 

Molars  (Grinders). — There  are  three  molars  on  each 
side  of  each  jaw,  twelve  in  all.  They  are  the  largest  of 
the  human  teeth,  and  indicate  the  important  position  they 
occupy  in  mastication  by  the  complicated  pattern  of  the 
chewing  surfaces,  which  consist  of  variously  developed 
and  arranged  cusps  with  interlying  grooves  and  depres- 
sions (Figs.  24  and  25).  The  molars  are  about  twice  the 
size  of  the  bicuspids,  and  in  comparing  their  crowns  it 
will  be  observed  that  the  two  molars  which  grow  in 
juxtaposition  to  the  bicuspids  are  not  very  much  unlike 
them ;  having  two  buccal  and  two  lingual  cusps.  The 
form  of  a  molar  is  often  described  as  cuboidal,  but  as  its 
mesial-distal  diameter  is  greater  than  the  labial-lingual, 
the  term  "  prismatic  "  would  probably  be  more  appropri- 
ate. 

The  first  is  usually  called  by  the  laity  the  ''  six  year 
molar,"  the  second  the  twelve  year  molar,  and  the  third 
"the  wisdom  tooth."  The  upper  molars  have  three  roots, 
while  the  lower  liave  but  two. 

The  upper  molars  possess  corresponding  characteristics 
yet  differ  in  certain  respects  from  each  other.  Of  the 
four  cusps,  as  is  the  case  in  the  bicuspids,  the  buccal  are 
better  developed  than  the  lingual  and  the  mesial-buccal 
cusp  is  the  longest  and  sharpest. 

The  cul)oidal  shaped  first  upper  molar  is  the  largest 
tooth  of  this  set  and  is  more  nearly  square  in  form.  The 
second  molar  shows,  on  cross  section,  a  tendency  to  a 


60 


SPECIAL  ANATOMY  OF  THE  TEETH. 


triangular  form,  which  is  sometimes  better  developed  in 
the  third  tooth.     A  peculiarity  of  the  first  molar  is  the 


Mesial. 


Lingual. 


Buccal. 


Distal. 

Fig.  24.— Chewing  surface  of  the  first  upper  molar :  a,  mesial-buccal  cusp. 
6,  buccal  groove,  c,  central  fossa,  rf,  distal-buccal  cusp,  e,  distal  groove.  /, 
lingual  groove,  g,  distal-lingual  cusp,  ft,  a  small  fifth  cusp  (cingulum).  i, 
mesial-lingual  cusp,    k,  mesial  groove. 


Distal. 


Lingual.      Ji- 


Mesial. 


Fig.  25.— Chewing  surface  of  the  first  lower  molar,  a.  distal-buccal  cusp. 
h,  buccal  cusp,  c,  central  groove,  d,  buccal  fossa,  e,  mesial-buccal  cusp.  /, 
mesial-lingual  cusp,  g,  central  groove.  /i,llngTial  groove,  i,  distal-lingual  cusp. 


frequent  appearance  of  a  fifth  cusp  at  the  mesial-lingual 
edge  (Fig.  24,  h). 


THE  PERMANENT  TEETH.  61 

This  tooth  is  conical  in  shape,  i.  e.,  broader  at  the 
chewing  surface  than  at  the  neck.  Therefore,  in  the 
application  of  rings  and  crowns  a  considerable  portion  of 
the  wall  must  be  ground  down,  and  a  large  tuljerosity  on 
the  neck  must  be  cut  a^ay  with  special  care. 

The  buccal  wall  has  a  convex  surface,  w'ith  a  groove 
extending  between  the  two  buccal  cusps  (buccal-groove), 
dividing  it  into  a  broad  and  long  anterior,  and  a  narrow 
and  short  posterior  portion.  This  arrangement  alone, 
excluding  all  other  characteristics  is  sufficient  to  dis- 
tinguish the  right  from  the  left  molars.  This  buccal 
groove  is  a  frequent  seat  for  the  beginning  of  caries  and 
must  not  be  overlooked  in  examination. 

There  is  also  a  groove  on  the  lingual  aspect,  the  lingual 
groove,  which  beginning  between  the  lingual-mesial  and 
the  lingual-distal  cusps  reaches  nearly  to  the  neck  of  the 
tooth.  The  anterior  or  mesial  portion  of  the  lingual  wall 
presents  the  before  mentioned  fifth  cusp.  This  tooth  has 
three  roots,  a  strong  diverging  one  which  points  toward 
the  palate  and  two  weaker  ones  which  are  inserted  in  the 
buccal  portion  of  the  alveolar  process.  Of  the  three  root 
canals,  the  one  which  is  nearest  to  the  palate,  is  the  widest 
and  most  easily  accessible  to  a  sound  or  canal  plugger, 
the  other  canals  are  smaller  and  often  constricted  laterally. 
For  the  details  of  these  canals  see  the  chapter  on  corrosion 
anatomy  (Page  51). 

The  second  upper  molar  differs  from  its  preceding 
fellow  in  the  fact  that  the  disto-lingual  cusp  is  smaller 
and  in  many  cases  entirely  absent.  Hence,  often  only 
three  cusps  are  present  two  buccal  and  one  lingual,  and 
in  which  case  the  lingual  groove  is  usually  missing.  The 
roots  compared  with  those  of  the  first  molar  are  somewhat 
weaker  and  tend  more  to  point  in  the  distal  direction. 
They  also  vary  more  often  in  form  than  do  the  roots  of 
the  first  molars  and  not  infrequently  a  deformity  of  the 
originally  separated  roots  is  observed.  Therefore,  it  may 
at  times  be  impossible  to  locate  more  than  two  root  canals. 

The  third  upper  molar,  however,  is  subject  to  the 
greatest  variations.     All  the  various  grades  of  develop- 


62 


SPECIAL  ANATOMY  OF  THE  TEETH. 


Lingual. 


Buccal. 


ment  may  be  met  with  between  a  well  developed  molar 
and  a  simple  peg  tooth,  and  there  are  many  cases  in  which 
this  tooth  never  reaches  the  stage  of  eruption.  In  the 
stunted  forms  the  roots  are  also  poorly  developed;  they  may 
however,  be  divided  into  three  distinct  parts  and  show,  like 
the  crown,  all  the  possible  deviations  from  normal.  Fig. 
26  illustrates  the  arrangement  and  the  relative  size  of 
the  upper  bicuspids  and  molars  as  seen  in  a  normal  jaw. 

The  lower  molars  are 
similar  in  construction  to 
the  upper  ones,  with  the 
exception  that  they  are 
square  in  shape  and  have 
two  roots.  In  these  teeth 
the  lingual  cusps  are 
higher  than  the  buccal 
cusps,  which  is  contrary 
to  the  form  of  the  cusps 
of  the  upper  molars. 

The  first  lower  molar, 
excepting  its  antagonist, 
is  the  largest  grinding 
tooth,  and  differs  from 
the  upper  one  by  the 
possession  of  three  buc- 
cal and  two  lingual  cusps. 
These  cusps  surround,  as 
seen  in  Fig.  25,  a  central 
depression  into  which  the  grooves  run.  The  buccal  wall 
shows  a  groove  of  considerable  depth  which  reaches  half 
way  up  to  the  crown.  The  lingual  surface  is  smooth  and 
without  grooves.  The  roots  lie  back  of  each  other,  i.  e., 
one  on  the  mesial  and  the  other  on  the  distal  side ;  they 
are  not  straight  but,  on  the  contrary,  are  curved  back- 
wards. The  mesial  root  is  somewhat  weaker  and  more 
circular  than  the  considerably  flattened  distal  root,  there- 
fore an  instrument  is  easily  passed  into  the  distal  but  with 
difficulty  into  the  mesial  root. 

The  second  lower  molar  has  a  decidedly  smaller  cir- 


>^ 


Fig.  26.— Arrangement  and  relative 
size  of  the  upper  bicuspids  and  molars  : 
a,  first  bicuspid  ;  b,  second  bicuspid;  c, 
first  molar;  d,  second  molar ;  e,  third 
molar. 


THE  PERMANENT  TEETH.  63 

cumference  than  the  first.  It  has  four  cusps,  and  in  rare 
cases  a  fifth  disto-buccal  cusp  raay  be  present.  This  tooth 
is  subject  to  greater  variation  in  form  than  the  former. 
In  exceptional  cases  after  extraction,  the  second  lower 
molar  has  been  found  to  possess  but  one  root  instead  of 
two.  The  root  canals  resemble  those  of  the  first  molars. 
The  third  lower  molar,  or  wisdom  tooth,  resembles  its 
neighbor  more  than  is  the  case  in  the  upper  jaw,  usually 
however,  it  is  somewhat  smaller,  very  rarely,  at  any  rate 


Lingual.        JS^^i^^^K"    '  ^  -  %     Buccal 


Fig.  27.— Arrangement  and  relative  size  of  the  lower  bicuspids  and  molars: 
a,  first  bicuspid;  6,  second  bicuspid;  c,  tirst  molar;  d,  second  molar;  e,  third 
molar. 

more  infrequently  than  in  the  upper  jaw,  this  tooth  is 
reduced  in  size  to  that  of  a  peg  tooth.  On  the  other  hand 
tlie  grinding  surface  is  sometimes  surprisingly  complicated 
for  it  may  have  four,  five  or  even  more  cusps.  This 
tooth  has  either  the  normal  number  of  two  roots  or  an 
abnormal  number  of  from  three  to  five ;  occasionally  the 
roots  are  fused  into  one  stem.  When  the  roots  are  of 
large  size,  extraction  may  present  considerable  difficulty 
for  in  this  region  the  bone  is  thickened  by  the  oblique 


64  SPECIAL  ANATOMY  OF  THE  TEETH. 

and  mylohyoid  lines.  The  root  canals  like  in  all  other 
teeth  correspond  to  the  form  of  the  roots.  These  teeth 
are  generally  quite  susceptible  to  decay  and  their  tooth 
germs  even  at  the  time  they  make  their  appearance  fre- 
quently present  carious  changes. 

Figure  27  shows  the  arrangement  and  relative  size  of 
the  lower  bicuspids  and  molars.  This  specimen  is  obtained 
from  the  same  normal  and  powerful  skull  as  is  the  one 
shown  in  Fio-ure  26. 

THE  DECIDUOUS  TEETH. 

(See  Plate  4,  lower  picture  and  Figure  28.) 

The  temporary  set  consists  of  twenty  teeth  wdiich  are 
arranged  as  follows : 


20 


There  are  in  all  8  incisors  (I),  4  cuspid  (C)  and  8  molar 
(M)  teeth.  These  molar  teeth  resemble  the  permanent 
molars  with  the  exception  of  being  smaller  and  lighter  in 
color.  They  also  possess  at  their  necks  a  more  prominent 
tubercle  than  the  permanent  ones. 

The  incisor  and  the  cuspid  teeth  of  both  the  upper  and 
the  lower  jaws  equal  in  number  the  corresponding  teeth  in 
the  permanent  set.  There  are  four  in  each  jaw  and  there- 
fore eight  in  all.  They  also  resemble  their  j^ermanent 
successors  in  form  except  that  they  are  relatively  shorter 
so  that  their  length  almost  equals  their  width,  while  their 
simple  roots  are  more  rounded  and  more  conical  in  shape. 

Two  molar  teeth  lie  next  to  the  cuspid  teeth  on  both 
sides  and  accordingly  there  are  altogether  eight  in  number. 
The  first  primary  molars  of  both  the  upper  and  lower  jaws 
plainly  show  variations  from  the  characteristics  of  the 
permanent  teeth,  and  resemble  the  molars  of  the  anthro- 
poid monkeys.  The  grinding  surface  of  the  first  tempo- 
rary molar  is  especially  interesting ;  it  consists  of  a  buccal 


MCI 

I    C    M 

2      12' 

2    12 

2      12 

2    12 

THE  ARTICULATION  OF  THE  TEETH. 


65 


and  lingual  ledge  which  contains  a  number  of  notches. 
The  meso-labial  border  has  also  an  accessory  cusp.     The 
roots  usually  consist  of 
one    palatine   and    two 
buccal  roots,  which  have 
grown  together. 

The  second  upper 
molar  resembles  the  first 
permanent  molar,  and 
is  indeed  a  diminutive 
model  of  it. 

The  first  lower  tem- 
porary molars  carry  from 
4—5  cusps  which  are 
grouped  around  two  de- 
pressions. As  mentioned 
above  an  additional  cusp 
may  occur  on  the  meso- 
labial  border.  These 
teeth  possess  two  roots. 
The  second  lower  molars 
resemble  the  first  per- 
manent molar,  except- 
ing that  they  are  smaller 
in  size ;  they  too  have  two  roots.  In  Fig.  28  the  upper 
and  lower  rows  of  milk  teeth  are  shown. 


Fig.  28.— The  milk  teeth  seen  from 
above:  a,  uppt-r:  6,  bjwer  tooth  rows.  In 
comparison  with  the  permanent  tooth 
rows,  the  curvature  of  the  milk  set  of 
teeth  is  more  nearly  that  of  a  semi-circle. 


THE  ARTICULATION  OF  THE  TEETH. 

The  two  rows  of  adult  teeth,  which  are  practically  horse 
shoe  shaped,  do  not  equal  eacli  other  in  size  and  form,  but 
as  is  seen  in  Fig.  28,  the  upper  is  the  larger  and  extends 
on  all  sides  beyond  the  lower  row. 

In  the  act  of  mastication  the  incisor  teeth  glide  past 
each  otlier  like  the  blades  of  a  pair  of  scissors,  the  lower 
passing  back  of  tlie  upper  teeth,  while  the  cusps  of  the 
bicuspids  and  molars  of  both  jaws  alternately  strike  the 
depressions  of  their  antagonists.  The  teeth  arc  .so  arranged 
in  size  and  position  that,  with  the  exception  of  the  lower 
5 


66 


SPECIAL  ANATOMY  OF  THE  TEETH. 


PLATE   5. 

Fig.  1. — Longitudinal  section  of  a  tooth-root  and  the  alveolus :  a. 
Dentin.  6.  Cementum.  c.  Periosteum  in  which  the  arteries  and  veins 
are  indicated  by  blue  and  red  colored  areas,  d.  Alveolus  with  many 
transversely  and  e,  longitudinally  cut  Haversian  canals. 

Fig.  2. — Cross  section  of  the  oral  mucous  membrane.  Injected 
preparation,  a.  Epithelium.  &.  Mucous,  from  the  wide  meshed  vascular 
net-work  of  which,  capillary  loops  arise  into  the  papillae. 

central  incisors  and  the  upper  third  molars,  each  tooth  in 
articulating  occludes  with  two  opposing  teeth.  This  is 
due  to  the  fact  that  the  incisor  and  cuspid  teeth  of  the 
upper  set  are  decidedly  wider  than  those  of  the  lower  set, 
thus  causing  the  upper  molars  to  set  further  back  in  the 
jaw  than  the  lower  molars.  The  first  upper  bicuspid 
touches  with  its  mesial  masticating  surface  the  distal 
portion  of  the  first  lower  bicuspid,  and  with  its  distal  part 


Fig.  29.— Articulation  of  the  two  tooth-rows.    Lateral  view. 


it  comes  in  contact  with  the  mesial  portion  of  the  second 
lower  bicuspid.  This  arrangement  of  the  bicuspid  teeth 
is  also  true  of  the  molars  excepting  that  the  displacement 
is  not  so  great. 

It  is  very  important  to  remember  these  simple  relation- 
ships, for  without  a  knowledge  of  them  it  is  impossible  to 


Vab-o. 


■'')'— f  •?'%■:  ■"'■'•A 


""H'l:'::# 


'"^■'M 


•^■A 


'^: 


Mg.l. 


Piff.Ji. 


HISTOLOGY.  67 

manufacture  properly  articulating  artificial  teeth  which 
have  a  natural  appearance.  Fig.  29  shows  the  normal 
articulations  of  the  teeth. 

HISTOLOGY, 

THE  MUCOUS  MEMBRANE  OF  THE  MOUTH. 

The  outer  skin  ( integumentum  commune )  merges 
gradually  into  the  mucous  membrane  of  the  mouth 
(mucosa  oris)  at  the  red  portion  of  the  lips,  and  the 
corium  of  the  true  mucosa  is  a  continuation  of  the  corium 
of  the  skin,  from  the  epidermic  covering  of  which  the 
epithelium  is  derived.  The  name  mucosa  is  employed 
because  of  the  large  number  of  mucous  and  albumin 
excreting  glands  which  that  tissue  lodges.  The  intense 
red  color  is  very  noticeable  and  is  due  to  the  rich  vascular 
system  and  the  transparency  of  the  upper  layer.  On  the 
tongue  this  red  color  blends  into  gray,  for  the  epithelium 
is  thicker  on  that  organ  than  in  the  other  portions  of  the 
oral  cavity. 

The  mucous  membrane  forms  (according  to  von  Ebner, 
Kollikers  Handbuch  der  Gewebelehre)  a  tight  and  elastic 
layer  from  220  to  450  n  in  thickness  with  numerous  papillae 
on  its  upper  surface,  which  resemble  those  of  the  skin.  (See 
Plate  5,  Fig.  2).  The  epithelium  over  the  papillae  is 
smooth,  excepting  on  the  tongue  where  little  prominences 
covered  with  epithelium  form  the  filiform,  fungiform, 
foliate,  and  circumvallate  papilloe. 

The  submucosa  passes  nearly  everywhere  gradually 
into  the  true  mucosa  without  a  positive  line  of  demar- 
cation. Loose  connective  tissue  is  found  in  large  quantities 
only  in  the  areas  where  mucous  membrane  is  freely  mov- 
able, as  on  the  floor  of  the  mouth,  the  fra?na  of  the  lips 
and  tongue,  and  it  too  merges  gradually  into  the  denser 
connective  tissue  of  the  mucosa.  The  mucosa  of  the 
cheeks,  gums  and  tongue  is  somewhat  diiferently  con- 
structed, for  in  these  regions  the  submucosa  contains  a 
greater  or  less  number  of  mucous  and  albumin  excreting 
glands  which  lie  crowded  together.     In  certain  locations 


68  HISTOLOGY. 

FIGURE  30. 

Longitudinal  section  of  a  molar.  S,  enamel ;  D,  dentin  ;  C,  cemen- 
turn;    P,  pulp  cavity  (from  Sobotta). 

where  these  glands  are  absent,  as  for  example  in  the 
neighborhood  of  the  alveolar  processes  and  in  certain 
situations  in  the  gumSj  the  submucosa,  which  is  homo- 
geneous in  appearance,  is  fastened  directly  to  the  peri- 
osteum without  any  noticeable  intervening  substance. 

The  connective  tissue  of  the  submucosa  is  arranged  in 
bundles,  the  thickness  of  which  varies  from  4  to  11, mm. 
Some  lie  parallel,  others  vertical  and  still  others  obliquely 
to  the  surface,  an  arrangement  which  forms  a  felt  like 
structure.  In  the  true  mucosa  these  bundles  of  tissue 
become  finer  and  in  the  papillse  they  lie  with  the  elastic 
fibres  as  fine  fibrillte  on  the  homogeneous  ground  sub- 
stance. The  fibrillge  are  often  associated  with  branching 
cells  of  the  loose  connective  tissue. 

The  cellular  elemeuts  of  the  mucous  membrane  of  the 
mouth  consists  of  a  rich  supply  of  leucocytes.  The  tunica 
propria  of  the  mucosa  of  the  gums  is  especially  the  seat  of 
physiological  leucocytic  infiltration  and  particularly  so  in 
the  neighborhood  of  the  back  molars.  True  glandular 
tissue,  however,  is  not  met  with  until  further  back  in  the 
mouth  where  in  the  tonsils  it  reaches  its  highest  form  of 
development. 

In  the  submucous  connective  tissue  the  blood-vessels 
(see  Plate  5,  Fig.  2)  form  a  wide  meshed  network,  from 
which  capillaries  supply  the  papillee.  The  vessels  form 
simple  vascular  loops  in  the  papillae  of  the  hard  palate 
and  of  the  floor  of  the  mouth,  while  a  capillary  network 
penetrates  the  papillae  of  the  gums  and  lips.  The  blood 
is  carried  away  by  a  small  vein  which  forms  at  the  center 
by  this  network. 

The  branches  which  arise  from  the  nerves  in  the  sub- 
mucosa form  a  plexus  in  the  mucosa  which  gives  the 
following  branches : 

1.  Medullated  fibers  with  or  without  end  bulbs. 

2.  Non-medullated  fibers  Avhich  build  a  subepithelial 


Fig.  30. 


THE  HARD  AND  SOFT  DENTAL  TISSUES.         69 

network,  from  which  fibers  with  slightly  enlarged  ends 
penetrate  between  the  epithelial  cells. 

3.  Fibers  the  branches  of  which  are  found  everywhere 
in  tiie  submucosa,  mucosa,  glands,  and  blood-vessel  walls. 

The  lymphatics  build  a  wide-meshed  reticulum  in  the 
deepest  layers  of  the  submucosa  which  connects  with  the 
true  mucosa  through  anastomosis  with  a  finely  meshed 
network  from  which  small  branches  with  closed  ends 
penetrate  into  the  papillae.  The  lymph  capillaries  of  the 
mucous  membrane  lie,  as  is  the  case  in  the  skin,  at  a 
deeper  level  than  do  the  blood  capillaries. 

The  epithelium  of  the  oral  cavity  is  of  a  stratified  pave- 
ment variety  (see  Plate  5,  Fig.  2).  The  cells  of  the 
deepest  and  youngest  layer  are  cylindrical,  those  of  the 
middle  layer  are  spherical,  while  the  elements  of  the 
uppermost  and  oldest  layer  are  flattened  and  compressed. 
The  outlines  of  the  latter  cells  is  that  of  a  rounded 
polygon.  The  nuclei  of  these  cells  are  plainly  seen  while 
their  cell  bodies  are  opaque  because  of  the  presence  of 
fine  granules.  The  upper  layer  of  cells  is  being  con- 
stantly shed  and  its  place  taken  by  the  layer  beneath. 
This  accounts  for  the  presence  of  such  elements  in  the 
sputum. 

The  absorptive  faculty  of  the  oral  mucous  membrane 
is  of  considerable  importance. 

THE  HARD  AND  SOFT  DENTAL  TISSUES. 

The  hard  portion  of  the  tooth  consists  of  three  different 
but  connected  structures,  namely,  the  dentin,  enamel,  and 
cementum  (see  Fig.  30).  The  enamel  being  a  product  of 
the  surface  epithelium  is  ectodermic  in  origin  while  the 
dentin  and  cementum  originate  in  the  mesoderm.  The 
soft  parts  of  the  tooth  are  limited  to  the  tooth  pulp  which 
occupies  the  central  or  pulp  cavity  of  the  tooth,  and  the 
pericemental  membrane  or  periosteum  (periodont)  which 
covers  the  roots. 

The  Dentin. — The  dentin  which  resembles  in  many 
respects   the   hard   part  of  bone,  constitutes   the  chief 


70 


HISTOLOGY. 


The    matrix    or 


structure  of  the  teeth  (Fig.  31).  It  is  covered  at  the 
crown  by  enamel  and  at  the  roots  by  cementum.  Its 
degree  of  density  is  midway  between  that  of  these  two 
substances,  it  being  harder  than  the  cementum  and  softer 
than  the  enamel.  On  longitudinal  section,  dentin  has  a 
gloss  like  that  of  silk.  Microscopical  examination  shows 
concentric  lines  (Owen)  in  the  coronal  portion  which  run 
almost  parallel  to  the  upper  surface,  and  interglobular 
spaces  which  lie  in  the  periphery.  The  so-called  granular 
layer  of  Tomes  occurs  near  the  junction  of  the  dentin  and 
cementum. 

ground  substance  is  calcified  and 
traversed  by  the  gelatin  yielding 
fibrils.  These  do  not  run  parallel 
to  the  dentinal  tubules  but  form 
layers,  which  depending  upon  the 
location  in  the  tooth  run  in  various 
directions.  The  author  agrees  with 
von  Ebner  that  they  form  lamellse 
which  follow  the  outer  contour  of 
the  tooth's  crown,  and  that  at  the 
roots  they  assume  a  more  cylin- 
drical shape  around  the  longitudinal 
axis. 

In  this  ground  substance,  which 
consists  then  of  a  calcified  mass  and 
many  gelatin  yielding  fibrils,  the 
dentinal  tubules  are  imbedded.  These  are  hollow  tubes  3—4 
mm.  in  wddth  which  radiate  in  a  spiral  manner  from 
the  pulp  cavity  to  the  periphery  (Welcker).  In  regard 
to  their  direction,  it  mav  be  generally  said  that  thev  are 
horizontally  arranged  in  the  roots  and  gradually  become 
vertical  toward  the  crown.  The  dentinal  tubules  are 
connected  with  each  other  through  numerous  minute 
branches. 

Concerning  the  subdivision  of  the  dentinal  tubule,  it 
may  be  stated,  that  soon  after  its  origin  it  branches  into  a 
second  tubule  which  runs  parallel  to  the  first.  This  sub- 
division gives  off  similar  branches,  but  of  smaller  caliber, 


Fig.  si.— Longitudinal 
section  of  a  bicuspid  tooth: 
a,  shows  all  the  structures 
of  the  tooth  ;  b,  shows  only 
the  dentin  in  order  to  in- 
dicate that  it  is  the  main 
substance  of  a  tooth. 


THE  HARD  AND  SOFT  DENTAL   TISSUES. 


71 


Surface  of  Pulp  Cavity. 

Fig.  32.— Branching  of  the 
dentinal  tubules.  Longitudinal 
section. 


as  it  runs  toward  the  periphery  (Fig.  32).  The  tubules 
which  have  diminished  considerably  in  size  upon  reach- 
ing the  edge  of  the  enamel  are 
lost  with  pear  shaped  terminals 
in  the  interglobular  spaces  and 
in  the  granular  layer,  or  they 
end  with  tapering  points  in  the 
ground  substance  of  the  dentin. 
Xot  infrequently  so-called  ter- 
minal loops  are  found  between 
branches  of  neiy-hboring  tubules. 
The  character  of  the  termina- 
tions in  the  enamel  deserve 
special  attention,  for  here  several 
of  the  tubules  develop  club 
shaped  ends  which  penetrate 
several  micromillimeters  into 
the  substance  of  the  enamel. 
Romer  as  well  as  Morgenstern 
believe  these  thickenings  to  be 
nerve  endings.  But  von  Ebner^  Rose  and  others  are  no 
doubt  correct   in   asserting  that    this  has   not   yet   been 

proven.  According  to  the 
careful  investigation  of 
Walkhoff  the  belief  in  the 
presence  of  dentinal  nerves 
is  today  more  nncertain 
than  ever. 

A  cross  section  of  a  den- 
tinal tubule  (Fig,  33)  shows 
a    round    limiting    sheath, 
the    so-called    "  Xeuniann's 
siieath "  which    is    calcified 
like  the  ground  substance. 
The  lumen  of  each  .sheath  is 
occupied  by  the   uncalcified 
To)nc.s\fibrcs.   That  the  structures  are  reallv  arranged  in  the 
dentin  as  just  described,  has  been  determined  both  by  Hoppe 
and  Koelliker.  By  destroying  all  organic  tissues  with  acids, 


a». 


Cd 


(9   -9 
9 


%«> 


Q/ . 


(» 


fe® 


'e  <9  <a)    d 


Fig.  ::::.^fr,,<^.rou..) 
tinal  tubule^.     Tlir  pakTin- 
sheaths  uf  Xeumann    and  the 
points  which  are  surrounded  by  the 
latter,  are  the  Hbers  of  Tomes. 


72  HISTOLOGY. 

they  were  able  to  isolate  in  the  fossil  teeth  of  mammals  such 
as  Neumann's  sheaths  in  the  form  of  minute  tortuous  tubes. 
Concerning  the  fibres  of  Tomes',  opinion  is  much  divid- 
ed, and  as  a  compromise  we  cite  the  view  which  seems 
most  tenable.  The  Tomes'  fibers  consist  of  prolonga- 
tions from  the  odontoblasts,  which  remain  uncalcified 
and,  being  elastic,  can  be  drawn  out  of  the  dentinal  tub- 
ules. The  nature  of  their  structure  has  not  yet  been  posi- 
tively determined  but  they  are  known  to  be  homogeneous 
in  appearance.  Their  function  on  the  one  hand  consists 
in  carrying  nourishment  centrifugally,  and  on  the  other, 
in  transmitting  sensation  centripetally.  They  may  also 
possess  an  additional  function  to  be  described  later,  which 

is  to  act  as  a  protective  or 
||U',:  1'  ^      at  least  as  a  reactive  agency 

Hill)'' if'  '  '    '  against  caries. 

SlMllwy^^itl'^^i^  '^^'^^  interglobular  spaces, 

P*vli%f^^O  which  lie  near  the  surface 

i!>4^^^^(^^Dfli^3^^  of  the   dentin  both  at  the 

;.-  ..  ■•{■•^iT^'^Wlll^J  crown   and    at    the    roots, 

y/'.;.'  ,.     .  '    .  :  i 't      ■•^•v  .       derive     their   name    irom 
Hffllr   ii  I     their  similarity  in  appear- 

mmmhAAL.L.....'..^.--i--...-^-.-^ — i— ^     ance  to  that  of  the  numer- 

FiG.    34.— Interglobular    spaces  of   the       niie    fneprl  o-lnl-mlpQ        TVipv 
dentin.  Longitudinal  section.  UUb    lUbeu  giuuuitib.       -i  uty 

represent  nothing  but  un- 
calcified dentin  which  has  retained  its  segmented  cal- 
cified lines.  The  spaces  themselves  contain  organic  matter 
and  uninterrupted  dentinal  tubules.  In  the  crown  these 
hollow  spaces  are  very  variable  in  arrangement  and  size. 
In  poorly  developed  teeth  they  are  much  larger  in  size 
than  in  the  healthy  teeth.  The  author  possesses  some  poorly 
developed  teeth  from  idiots,  the  dentin  of  which  is  nearly 
wholly  comprised  of  interglobular  spaces.  The  inter- 
globular spaces  of  the  roots,  which  consists  of  fine  and 
regularly  sized  globules  (granular  layer)  are  found  also  as 
a  rule  in  a  well  developed  tooth.  In  certain  areas  they  lie  in 
direct  contact  with  the  cementum,  while  in  others  a  thin 
layer  of  homogeneous  dentin  intervenes.  According  to  von 
Bibra,  dentin  possesses  the  following  chemical  constituents; 


THE  HARD  AND  SOFT  DENTAL   TISSUES. 


73 


Basic  calcium  phosphate 66.72 

Calcium  carbonate .    3.36 

Calcium  phosphate 1.08 

Sodium  salts 0.83 

Organic  matter 27.61 

Fat 0.40 

Calcium  fluorid Traces 

Therefore  dentin  consists  of  28.01  parts  of  organic  and  71.99  parts  of 
inorganic  substances. 

[This  table  of  chemical  constituents  does  not  agree,  with 
other  tables  of  von  Bibra  as  given  in  American  text- 
books— Ed.] 

The  Knamel. — Every  tooth  is  covered  by  a  cap  of 
enamel.  The  normal  enamel  has  a  shiny  yellowish  white 
color  which  may  sometimes  be 
bluish,  greenish,  brownish,  etc.  In 
favorable  lia^ht  we  recoo-nize,  even 
with  the  naked  eye,  the  enamel 
prisms  on  the  surface  of  the  tooth 
(perichymates)  (Fig.  35),  which  lie 
in  the  form  of  horizontal  rings 
around  the  crown. 

These  prisms  are  arranged  closely 
together  at  the  neck  and  the  further 
away  they  are  from  this  region  the 
greater  is  the  space  intervening  be- 
tween the  prisms.  ^  ^ 

The  enamel  is  covered  by  a  mem- 
brane or  cuticle  which  was  first 
described     by    Nasmyth.       It    is     ^J^ce^.-^Zllor^^^ 

easily  loosened  from  the  surface  of       the    pericbymates    (enamel 

the  tooth  by  a  few  minutes  applica- 
tion of  any  of  the  mineral  acids.  As  has  been  shown  by  a 
number  of  investigators,  organic  acids  also  aifect  this 
membrane ;  they  cause  the  enamel  cuticle  to  change  in 
color,  to  become  wrinkled  and  after  a  time  to  loosen. 
Koelliker  and  von  Ebner  believe  this  membrane  to  be  a 
cuticular  formation,  l)ut  AValdeyer  does  not  agree  with  this 
observation,  for  he  believes  that  he  saw  the  outlines  of 
epithelial  cells  upon  treating  this  structure  with  hydro- 


74  HISTOLOGY. 

chloric  acid  and  silver  nitrate.  Wedl,  J.  Tomes,  A. 
Tomes,  Baume  and  Magitot  believe  the  enamel  membrane 
is  homologous  to  the  crown  cement  of  certain  mammals. 
It  seems,  indeed,  that  the  root  cement  at  the  neck  of  the 
tooth  thickens  into  a  homogeneous  mass  which  is  continued 
into  the  enamel  membrane.  The  author,  however,  is 
inclined  to  accept  the  view  of  von  Ebner,  who  referring  to 
the  embryology,  states  that  the  enamel  membrane  is  derived 
from  the  ameloblasts,  and  that  at  no  period  of  develop- 
ment does  osteogenetic  tissue  occur  in  the  human  enamel. 

Enamel  differs  considerably  in  structure  from  dentin. 
It  consists  of  solid  hexagonal  or  polygonal  columns  or 
prisms.^  These  prisms  are  homogeneous  and  transparent. 
Through  the  action  of  acids,  both  organic  and  inorganic, 
one  can  readily  demonstrate  the  transverse  striation  which 
hithertofore  was  only  observed  and  reported  in  caries  and 
when  hydrochloric  acid  was  applied.  Such  cauterized 
prisms  on  account  of  the  alternate  dark  transverse 
striations  resemble  transversely  striped  muscle  fibres. 

The  enamel  prisms  are  joined  to  each  other  by  means 
of  an  interprismatic  cement  ( Corsica?  substance  ofWalkhoff), 
and  thus  constitute  one  solid  structure.  This  is  richer  in 
organic  matter  than  the  prisms  themselves,  for  it  is  pre- 
served for  a  longer  period  of  time,  and  according  to  von 
Ebner,  it  is  easily  stained  with  congo  solution  in  early 
life.  It  is  reasonable  to  assume  that  minute  currents  of 
liquid  traverse  the  interprismatic  substance,  for  not  only 
the  dentin,  but  also,  in  a  demonstrable  degree,  the  enamel 
is  more  fragile  in  devitalized  than  in  the  living  teeth. 

From  personal  investigation  the  writer  has  found  that 
the  direction  in  which  the  prisms  run  is  simpler  in  the 
lower  than  in  the  higher  orders  of  animal  life.  The 
haplodont  type  which  represents  the  simplest  formation, 
is  characterized  by  prisms  which  have  a  simple  S-curv- 
ature.  In  the  human  teeth  the  course  of  the  prisms  is 
usually  spoken  of  as  being  spiral ;  this  description,  how- 

^As  has  been  reported  by  Rohan,  even  the  enamel  of  the  lower  fish, 
which  was  formerly  considered  homogeneous  shows  a  prismatic  structure 
in  polarized  light. 


THE  HARD  AND  SOFT  DENTAL   TISSUES. 


75 


C  ^STl-'  \XTC:!\Tf*.V-^^^^ 


Fig.  36.— The  parallel 
lines  of  Retzlus  passing 
thrnugii  the  perichymates 
on  the  surface  of  the  enamel. 
Longitudinal  section  of  the 
enamel. 


ever,  is  not  absolutely  accurate,  as  the  spiral  is  a  dis' 

proportionate  one  in  Avhicli  tlie  main  curves  have  nunier 

oils    side  curvatures;  therefore  it 

is  best  to  consider  the  direction  of 

these  prisms,  as  irregularly  curled. 
Two  kinds  of  striated  patterns 

are    particularly    noticeable    on    a 

polished  longitudinal  section  of  the 

enamel,  but  we  wish  to  call  atten- 
tion to  a  third  striation  which  is 

present  upon  a  much  larger  scale, 

namely  the  brown  parallel    striae 

(contour  lines)  of  Relzias.      These 

occur    in    all    bunodont     animals 

whose  tooth  crowns  possess  peri- 

eliymates,  and,  less   distinctly,  in 

the    lophiodonts.       In    the    peris- 

sodactylic    and    the    artiodactylic 

solenodonts  the  contour  lines  do  not 

exist,  but  in  place  of  them  broad  contour  bands  are  seen. 

As  has  been  correctly  observed 
by  Baume,  the  brown  color  of  the 
contour  lines  is  due  to  the  pres- 
ence of  air  in  the  dried  sections. 
In  the  recent  preparations  the 
l:)rownish  discoloration  is  due  to 
the  presence  in  this  region  of  a 
greater  amount  of  interprismatic 
cement  which  is  less  calcified,  a 
view  with  which  von  Ebner  also 
concurs.  A  uniform  curvature 
of  the  prisms  also  assists  in  form- 
ing the  contour  lines.  Zsigmondy 
shows  ])reparations  in  which  hy- 
]>oplastic  growths  of  the  enamel 
coincided  with  the  contour  lines; 
this  argues  favorably  for  the  above 
observation. 
The  lines  of  Schreger  are  alternating  dark  and  light 


Fig.  37.— a,  dentin :  6,  enamel 
with  the  lines  of  Schreger.  Lon- 
gitudinal section.    Direct  light. 


16 


HISTOLOGY. 


bands  with  regular  interspaces,  which  traverse  the 
enamel  toward  its  surface  in  such  a  manner  as  to  give  it 
a  striated  appearance  (Fig.  37).  These  lines  are  not 
colored,  for  by  azimuthal  rotation  of  180°,  the  dark  bands 
become  light  and  the  light  dark  (as  was  determined  by 
Czermak).  Their  occurrence  is  considered  by  Linderer, 
with  whom  Koelliker  and  von  Ebner  agree  to  be  due 
to  alternating  uniform  curvatures  of  the  prismatic  bun- 
dles. The  lines  of  Schreger  may  be  seen  to  shimmer 
throuo^h  the  intact  enamel  of  the  teeth  of  the  beasts  of 
prey. 

We  apply  the  term  "zones"  to  the  markings  which  are 

seen  on  a  longitudinal  section 
of  the  enamel  under  high 
magnification.  They  are  sim- 
ply prismatic  bands  with 
uniform  alternating  curva- 
tures that  come  to  view  on 
longitudinal  section.  AVhen 
such  zones  consist  mainly 
of  longitudinally  arranged' 
prisms,  we  call  them  "para- 
zones  ; "  these  alternate  usual- 
ly with  zones,  the  prisms  of 
which  are  seen  in  cross  sec- 
tion and  which  are  called 
"  diazones."  von  Ebner'  ob- 
served and  proved  that,  as  a 
fact,  structural  relationships  exist  here  which  have  noth- 
ing in  common  with  the  striae  of  Schreger. 

In  certain  animals,  especially  in  the  carnivora  and 
rodents,  these  relationships  are  better  seen  than  in  man. 
The  incisor  tooth  of  the  squirrel,  for  instance,  shows  a 
classical  picture  of  this  zone  formation,  each  zone  being 
formed  by  a  single  prismatic  layer.  We  are  indebted  to 
J.  Tomes  for  a  masterful  description  of  this  condition. 
The  arrangement  of  these  zones  is  so  characteristic  of 
different  classes  of  animals  that  it  is  of  considerable  value 
1  von  Ebner,  Koelliker' s,  Handbuch  der   Gewebelehre,  1899,  page  89- 


Fig.  of.— Zones  of  the  enamel. 
a,  diazone ;  b,  parazone.  Longi- 
tudinal section. 


THE  HARD  AND  SOFT  DENTAL   TISSUES. 


77 


in  tracing  their  evolutionary  history  and  determining  their 
genesis. 

According  to  von  Bibra,  enamel  consists  of  the  follow- 
ing chemical  constituents  : 

Calcium  phosphate 89.82 

Calcium  carbonate 4.37 

Calcium  fluoride Traces 

Magnesium  phosj^hate 1.34 

Other  salts 0.88 

Organic  matter 3.39 

Fat ...    0.20 

Therefore  enamel  consists  of  96.41  per  cent,  of  inorganic,  and  3. 59 
per  cent,  of  organic  subst<ances. 

The  Cementum. — The  cementum  is  the  softest  of 
the  calcified  dental  substan- 
ces. Both  in  this  respect  and  P^                                  ^ 
histologically  it  closely  re-  "^    "  ""                    ,^ 
seml)les  bone.  c — —                     ^.           . 

It  decreases  in  thickness  *  ^  **  ""  **  d 
from  the  roots  toward  the  i^  .  ■■■^Att 
crown,  and  overlaps  the  °  '^I^^^^^^^^^^V^ 
enamel  as  a  thin  layer.  In  tJiKvW  ■  A''f  "^^  • 
animals,  especially  the  un-  [\\|r'Vi  ■,  ' 
gulates  and  rodents,  the  '". 
cementum  covers  the  crown  j 
of  the  molars  as  the  so- 
called  crown-cement.  ,                    ,,,.,...] 

In     the    thin     regions    its  Fio.  :;'J.~a,  ,lcnun;  '-,  interglobu- 

sfnictnrnl  formation   differs     lar  spaces  on  the  border  between  the 
biiucLUicU  lOiuicUiuu    luueift      dentin  and  cementum;  c,  cementum 

from     that     in     the     thicker  with    the    cement    bodies    and    the 

rp,,          ,  .                .            p  tibers  of  Sharpev  running  obliquely 

areas.      I  lie  tilin  portion  Ot  to    the  surface  of  the    dentin.    The 

,1                      ,  curved  lines  indicate  the  layer-like 

the  cement  appears    on   sec-  construction  of  the  cementum. 

tion  to  be  structureless  and 

diaphanous,  but  when    decalcified  and    stained    it  shows 

perpendicular  bundles  which  resemble  Sharpey's  fibers. 

Such  uncalcified  fibers  also  traverse  the  ground  sub- 
stance of  the  thicker  layers  of  the  cementum,  but  associ- 
ated with  them  are  seen  cement  corpuscles  which  differ 
from  the  bone  corpuscles  by  their  long  processes.  The 
processes  of  neighboring  cement  corpuscles  are  joined 


78  HISTOLOGY. 

PLATE  6. 
Histological  Preparations  of  the  Pulp. 

Fig.  1. — a,  ordinary  pulp  tissue  ;  b,  bundles  of  fibers  which  follow  the 
nerves  and  vessels ;  c,  small  blood-vessel  on  longitudinal  section ;  d,  longi- 
tudinal section  of  a  large  blood-vessel  filled  with  corpuscles ;  e,  odonto- 
blastic layer.     Longitudinal  section.     Hematoxylin — Eosin. 

Fig.  2. — a,  round  cells  of  the  pulp ;  b,  spindle  shaped  cells.  Longi- 
tudinal section.     Hematoxylin.     Highly  magnified. 

Fig.  3. — a,  ordinary  pulp  tissue  ;  b,  nerve  buudles  on  longitudinal 
section  ;  c,  blood-vessels  surrounded  by  nerve  bundles.  Longitudinal 
section.     Hematoxylin — osmic  acid. 

Fig.  4. — a,  nerve  bundles  on  cross  section  ;  6,  blood-vessels  surrounded 
by  bundles  of  nerves.  Cross  section  of  the  root-pulp.  Hematoxylin — 
osmic  acid. 

PLATE    7. 

Distribution  of  the  blood-vessels  of  a  young  cuspid  tooth.  The 
arteries  are  colored  red  and  the  veins  blue.  The  light  yellow  stripe  ou 
the  periphery  indicates  the  odontoblastic  layer.  Injected  preparation. 
Eeconstructed  from  serial  sections. 

PLATE  8. 

Fig.  1. — Section  through  the  border  between  the  dentin  and  the  pulp. 
a,  Tomes'  fibers  (redj  in  the  dentin  (yellow);  b,  pulp;  c,  odontoblasts; 
d,  Tomes'  fibers,  which  have  been  torn  from  the  dentinal  tubules.  Longi- 
tudinal section.  Koch's  hardening  process  (Canada-balsam).  Picric 
acid.     Carmin. 

Fig.  2. — Network  of  the  connective  tissue  in  the  embryonal  dental 
papilla.     Methylene  blue. 

Fig.  3. — Ameloblasts  (enamel  constructors)  in  activity,  a,  amelo- 
blasts;  6,  layer  of  prisms  with  cuticular  zone.  The  so-called  Tomes' 
ameloblastic  processes;  c,  intercellular  substance,  in  the  form  of  a  honey 
comb,  which  is  undergoing  dentification.  Hematoxylin — Eosin.  High 
magnification. 

Fig.  4. — Isolated  odontoblasts  (dentin  constructors),  a,  cell  bodies;  6, 
cell  nuclei;  c,  process  directed  toward  the  pulp;  f7,  process  directed 
toward  the  dentin  (Tomes'  fibers).    Methylene  blue.    High  magnification. 

together  so  that  an  uninterrupted  canal  system  traverses 
the  cementum.  According  to  B5decker  this  system  stands 
in  direct  communication  with  the  dentin.  Inasmuch  as 
the  cementum  is  composed  of  lamellae  which  are  arranged 
parallel  to  the  surface  its  appearance  is  similar  to  that  of 
bone.  Haversian  canals  are  not  present  in  the  cementum 
during  youth  but  occnr  later  in  life  associated  with  senile 
changes  and  hypertrophy  of  the  cementum. 

According  to  von  Bibra  the  chemical  constituents  of 
cementum  are : 


iab.6. 


Mg.l. 


Eiff.S. 


Fig.3. 


Fig.4,. 


Tab.  7. 


Tab 


Mcf.1. 


Fig.  4-. 


THE  HARD  AND  SOFT  DENTAL   TISSUES.         79 

Calcium  phosphate 58.73 

Calcium  carbonate 7.22 

Magnesium  phosphate 0.99 

Other  salts 0.82 

Organic  matter 31.31 

Fat 0.93 

Calcium  fluorid Traces 

Hence  cementum  consists  of  67.76  per  cent,  inorganic,  and  32.24  per 
cent,  of  organic  substances. 

The  Dental  Pulp. — The  central  cavity  of  the  tooth 
contains  the  dental  pulp,  which  is  the  persisting  but 
altered  dental  papilla,  and  which  during  development 
excreted  the  dentin.  It  is  divided  into  a  crown  and  a 
root.  The  former  assumes  the  outline  of  the  crown  only- 
it  is  smaller  in  size,  while  the  latter  extends  in  strands 
down  the  root  canals  to  the  apical  foramina.  The  color 
of  a  recently  removed  healthy  pulp  varies  from  whitish  to 
pale  rose.  Squeezing  the  pulp  causes  a  drop  of  fluid  to 
appear,  which  coagulates  in  the  air. 

Hi.stologically  (compare  Plate  6,  Figs.  1,  2,  3,  and  4, 
also  Plate  7,  and  Plate  8,  Fig.  1)  the  pulp  consists  of 
a  gelatinous  tissue  wliich,  however,  differs  from  that 
of  the  umbilical  cord,  because  it  contains  no  free  bundles 
of  connective  tissue.  Many  loose  fibrils  lying  across 
each  other  in  all  possible  directions,  are  embedded  in  a 
homogeneous  jelly-like  ground  substance,  M'hich,  according 
to  von  Ebner  are  supposed  to  be  gelatin-yielding  fibrils. 

The  majority  of  the  cells  possess  many  branches,  and 
are  :  (1)  Polygonal  cells ;  the  processes  of  which  may  be 
single  or  subdivided  and  connected  by  branches  with 
neighboring  cells.  (2)  Between  the  polygonal  cells  many 
round  cells  occur  in  the  young  pulp.  (Plate  6,  Fig.  2, 
rt).  (3)  Various  spindle  shaped  connective-tissue  cells 
(Plate  6,  Fig.  2,  h)  lie  on  the  nerves  and  blood  vessels. 
These  elements  accompany  connective-tissue  bundles  and 
appear  only  in  connection  with  the  nerves  and  blood 
vessels  which  they  serve  to  sujjport.  Elastic  fibres  do 
not  occur  in  the  pulp.  Aside  from  these  elements,  cells 
are  found  at  the  surface  of  the  pulp  with  large  nuclei 
W'hich   have    the    form    of   cylindrical   epithelium.      (4) 


80  HISTOLOGY. 

PLATE  g. 
Frontal  section  through  the  head  of  a  new-born  child. 
(Region  of  the  molars). 
a.  Digastric  muscle,     h.  Mylohyoid  muscle,  c.  Geniohyoid  aud  gen- 
ioglossus  muscles,  d.  Buccinator  muscle,  e.  Tongue.  /.  Masseter  muscle. 
g     Inferior  rectus  muscle,    h.  Inferior  oblique  muscle,    i.    Medial  rectus 
muscle,  fc.  Lateral  rectus  muscle.  I.  Superior  oblique  muscle,  m.  Superior 
rectus   muscle,    n.     Levator  palpebral  muscle,    o.  Mandibula.  p.  Tooth- 
germs,    q.    Sublingual   gland.    The  guiding  line  points  to  a  large  white 
spot  which  represents  the  deep  liugual  artery.  A  smaller  white  dot  lying 
in  the  medial  direction  indicates    the  submaxillary  duct.  r.  Gums  ot  the 
upper  jaw.  .9.  Nasal  septum,  t.   Inferior  turbinated  bone.    u.  Middle  tur- 
binated bone.  V.  Superior  turbinated  bone.  w.  Eye-ball.  x.  Papilla  of  the 
optic  nerve,  y.  Scalp,  z.  Falx  cerebri. 

Odontoblasts  (dentine  constructors)  (Plate  8,  Fig.  1,  c) 
which,  even  in  the  completed  tooth,  continually  tend 
to  calcify  the  periphery  of  the  pulp  ;  but  less  so  than 
during  the  developmental  period.  They  send  protoplasmic 
processes,  the  fibres  of  Tomes,  through  the  dentinal 
tubules,  and  are  separated  from  tlie  pulp  by  a  crowded 
layer  of  round  cells. 

Some  of  the  blood  vessels,  as  described  by  Weil,  enter 
the  pulp,  from  3  to  10  in  number,  in  a  groove  formed  by 
the  nerve  bundles,  while  other  vessels  undoubtedly  enter 
through  a  tube-like  formation  of  the  nerve  bundles.  They 
divide  below,  and  in  the  odontoblastic  layer,  into  capil- 
laries from  which  veins  carry  oif  the  venous  blood.  Plate 
7  presents  a  reproduction  of  the  course  of  the  blood- 
vessels as  was  seen  in  a  large  number  of  serial  sections. 

As  was  stated  above,  the  oierves  of  which  there  are  five 
or  ten  bundles,  enter  with  the  blood-vessels,  and  at  the 
crown  of  the  pulp  spread  out  in  a  richnnastomosis.  Near 
the  surface  of  the  pulp  they  become  unmedullated  and 
penetrate  the  cells  of  the  odontoblastic  layer  as  fine  prim- 
itive fibres.  In  spite  of  careful  and  conscientious 
attempts  to  corroborate  the  findings  of  Riimer  and  Mor- 
genstern,  the  writer  was  unable  to  trace  the  nerves  into 
the  dentin.  Nor  was  he  able  to  confirm  Boedecker's 
observation  that  lymphatics  are  present  in  the  pulp  tissue. 
On  the  contrary  this  tissue  is  everywhere  free  of  lacunse. 
Even  in  cross  section  of  the  root  pulp  (Plate  6,  Fig.  4,) 


Tab.  9. 


-k 

—  i 

—  A 

~~9 


-f 

-  e 
d 


THE  BARD  AND  SOFT  DENTAL   TISSUES.         81 

where  a  lacuna  is  least  likely  to  escape  notice,  nothing 
resembling  a  lymph-vessel  was  to  be  detected. 

Calcareous  concretions  are  often  found  in  normal  pulps, 
especially  in  advanced  ago.  They  occur  partly  as  granules 
which  are  deposited  in  the  blood-vessel  walls  or,  more 
frequently  they  form  globules  which  on  section  show  a 
number  of  layers  concentrically  arranged  like  in  an  onion. 
Late  in  life  the  pulp  tissue  is  substituted  by  dense  con- 
nective tissue  in  which  only  a  few  cellular  elements 
remain. 

The  Root  Membrane  (Periosteum,  Periodon- 
tium).— (Plate  5,  Fig.  1,  c).  The  periosteum  forms  a  com- 
paratively thin  membranous  layer  between  the  cementum 
of  the  tooth  and  the  bone.  This  root  membrane  is  not  wholly 
identical  with  the  ordinary  periosteum,  either  histologically 
or  physiologically.  It  assists  in  holding  the  tooth  in  place, 
yet  allows  it  a  certain  amount  of  movement.  Malassez 
considers  this  movement  to  be  due  to  a  joint  formation  in 
which  he  characterizes  the  periosteum,  and  not  altogether 
incorrectly,  as  the  alveolar  ligament. 

The  alveolar  ligament  represents  the  continuation  of 
the  above  described  bundles  of  fibrous  tissue  which 
traverse  the  cementum  perpendicularly  to  its  surface,  and 
then  pass  over  to  the  bony  alveolus  to  penetrate  it  as  the 
fibres  of  Sharpey.  At  the  dental  cervix  these  fibres 
radiate  toward  the  bone  in  nearly  a  horizontal  direction, 
but  as  the  tips  of  the  roots  are  approached,  according  to 
many  authors,  their  direction  becomes  more  and  more 
oblique  so  that  the  tooth  appears  to  be  suspended  in  a 
socket  by  thousands  of  cables.  One  is  not,  however, 
always  fortunate  enough  to  see  these  relations  so  clearly 
for,  on  the  contrary,  only  a  maze  of  connective-tissue 
fibres  is  usually  seen.  Firm  bands  of  union  exist  between 
tlie  alveolar  border  and  the  neck  of  the  tooth  which  form, 
according  to  Koelliker,  the  circular  ligament. 

Loose  connective  tissue  lies  between  these  tight  bands, 

which  is  especially  abundant  at  the  tips  of  the  roots  where 

it  furnishes  protection  to  the  entering  nerves  and  blood 

vessels.     The    root  membrane   is    richly   supplied   with 

6 


82  PHYSIOLOGY. 

nerves  and  blood-vessels.  In  certain  areas  the  latter  form 
characteristic  vascular  glomeruli,  which  were  first 
described  by  Wedl. 

Of  especial  interest  are  the  epithelial  nests  (masses  epi- 
theliaux)  which  are  disseminated  more  or  less  abundantly 
throughout  the  above  described  tissue.  They  represent 
separated  fragments  from  the  epithelial  layer  (Von  Brunn) 
which  is  concerned  in  the  development  of  the  roots. 
These  fragments  may  cause  the  formation  of  periosteal 
cysts,  etc. 

PHYSIOLOGY, 

THE  DEVELOPMENT  OF  THE  TEETH. 

Plate  8,  Figs.  2,  3,  and  4,  also  Plates  9,  10,  11,  and  12. 
The  human  embryo  prepares  for  the  development  of 
teeth  about  the  fourteenth  day.     At  this  time  the  tongue 

is  already  probably  formed  but 
the  rudiments  of  the  lips  and 
jaws  form  as  yet  only  a  smooth 
mass,  while  the  Meckel's  carti- 
lage is  indicated  only  by  a  few 
and  scattered  round  mesodermic 
cells.  At  this  time  the  ectoderm 
of  the  embryonal  oral  cavity 
passes  down  into  the  mesoderm 
Fig.  40— ( \tcur(iiiif;toKosc)     of  the  rudimentary  iaws,  forra- 

a    Entrance  to   tlie    month    b        .  ,  i   •    *;      •,       /i^- 

The^udlmeuta^vlo^\e^Jrl^\.   <.       lUg  a  narrOW  band  mto  it.     (-Tig. 

inlme?OT|aT'' '''"'"" ^^''-  ''■     40  d).    Since  this  epithelial  band, 

in  the  course  of  development, 
produces  the  enamel,  it  was  termed  the  enamel  organ  l>y 
Koelliker ;  with  regard  to  its  shape  it  was  called  by 
Waldeyer  and  Hertwig,  the  enamel  band. 

The  enamel  organ  gradually  undergoes  longitudinal 
division,  the  front  part  grows  perpendicularly  downward 
and  forms  the  lip  groove,  which  separates  the  lip  from  the 
jaw  germ.  The  posterior  part  grows  in  a  horizontal 
direction  backward  and  becomes  specialized  into  the  tooth 
germ,  it  is  therefore  the  true  tooth-band.     (Fig.  41,  A). 


THE  DEVELOPMENT  OF  THE  TEETH. 


83 


After  it  has  built  the  upper  and  lower  maxillary  emi- 
nences, this  tooth  band  sends  ten  bud  like  eminences  into 
the  mesoderm  ;  these  are  the  germs  for  the  milk  teeth. 
The  mesoderm,  however,  does  not  remain  inactive  during 
this  time,  it  sends  connective-tissue  papillae,  the  origin  of 
the  future  pulp,  toward  these  eminences  and  indents  them. 
These  invaginations  are  not  in  the  plane  of  the  tooth  band 
but  to  one  side  and,  as  Rose  properly  described,  in  the 
upper  jaw  from  above  backward,  and  from  below  forward  ; 
in  the  lower  jaw  from  below  backward,  and  from  above 


Fig.  41.— o.  Entranee  to  the  mouth.  FiG.  42.— a.  Entrance  to  the  mouth. 

h.  Rudimentary  lower  jaw.  c.  Rufli-  6.     Lower  jaw.    c.     Upper   jaw.    rf. 

mentary  upper  jaw.  d.  Rudimentary  Lower  lip.     e.  Upper  lip.  /.    Labial 

lower  lip.  f.  Rudimentary  upper  lip.  sulcus,    g.    Labial   sulcus  band.   h. 

f.    Labial  sulcus,    p.     Labial  sulcus  Tooth-band.  i.Tooth  papillae, 
band.    h.  Tooth-band. 

forward.  Depending  upon  this  arrangement  the  tempo- 
rary teeth  germs  lie  nearer  the  periphery  of  the  maxillary 
eminence  to  permit  the  tooth  band  to  spread  without 
hindrance  in  the  lingual  direction  for  the  upbuilding  of 
the  permanent  teeth  (Fig.  42,  i). 

The  germs  of  the  deciduous  teeth  are  originally  joined 
to  the  tooth  band  by  means  of  a  Avide  neck.  But  as 
development  progresses  this  neck  is  drawn  out  and 
lengthened   and   in  areas   the  mesodermic  tissue   grows 


84  PHYSIOLOGY 

PLATE  10. 

Fig.  1. — a.  Tooth-germ  in  three  different  stages  in  one  preparation. 
b.  Enamel-organ,  which  becomes  invaginated  by  the  growing  mesodermic 
cells,  c.  These  mesodermic  cells  have  formed  here  the  tooth-papilla 
(dentiu-germ).  d.  Enamel  pulp,  which  e.  is  surrounded  by  the  tooth  sac. 
/.  Connecting  band.  g.  Epithelium  of  the  oral  mucous  membraue. 
Hematosylin-Eosin,  with  retouche. 

Fig.  2. — Tooth-germ.  a.  Tooth-papilla,  b.  Enamel  pulp.  c.  Outer 
epithelial  layer  of  the  same.  d.  Inner  epithelial  layer  of  the  same, 
e.  Connecting  bridge  between  primary  and  secondarj'  enamel  germs. 
/.  Secondary  enamel  germ.  g.  Connecting  baud.  h.  Epithelium  of  the 
oral  mucosa.    Hematoxylin-Eosin. 

through  it.  Hence  the  connective  bridge,  as  the  neck  is 
called,  consists  of  a  greater  or  less  number  of  fine  con- 
nective fibers. 

In  the  course  of  further  development  the  tooth  band 
loses  its  smooth  surface  and  its  compactness,  irregular 
thickenings  develop  which  are  alternately  perforated  like 
a  sieve.  Only  its  posterior  portion  still  possesses  a  layer 
of  smooth  epithelium  ;  in  this  position  a  club-like  thick- 
ening grows  toward  the  tongue  which  is  the  germ  for  the 
first  permanent  molar  tooth.  To  one  side,  toward  the 
lips,  a  row  of  successive  thickenings  now  arise  in  the 
tooth  band  from  which  originate  the  remaining  teeth  of 
the  second  dentition.  Here,  as  in  the  case  of  first  teeth, 
connective-tissue  papillae  press  against  the  knotty  thick- 
enings so  that  sometimes  the  epithelial  layer  fits  like  a 
hood  to  the  connective-tissue  eminence. 

The  germ  for  the  permanent  incisors  develops  in  about 
the  sixth  fetal  month.  The  germs  for  the  grinding  teeth 
which  are  postembryonal  in  development,  develop  during 
the  first  year  of  life.  The  further  destiny  of  the  tooth 
band  consists  in  an  increased  perforation  with  the  result 
that  it  loses  more  and  more  of  its  texture.  Nests  of 
epithelium  remain  imbedded  in  the  connective  tissue 
which  may  later  develop  into  cysts,  atheromata  and  other 
growths.  There  may  also  occur  an  abnormal  develop- 
ment of  enamel  and,  indeed,  it  has  not  rarely  been 
observed  that  connective-tissue  proliferation  occurs  in  such 
epithelial  nests  analagous  to  normal  tooth  construction, 


\^': 


f 1^ 


Tab. 10. 


"  c 
-b 


'?S 


Eiff.2. 


f- 


b  ^ 


a. 


I 

e 


lig.l. 


THE  DEVELOPMENT  OF  THE  TEETH.  85 

from  which  more  or  less  well  developed  supernumerary 
teeth  may  arise. 

The  tooth  bands  are  separated  from  their  surroundings 
by  the  tootli  sac,  a  connective-tissue  envelope,  which  con- 
sists of  two  layers,  one,  the  inner  which  lies  directly  upon 
the  tooth  germ,  consists  of  loose  connective  tissue  with 
many  blood-vessels,  and  the  other,  the  outer  layer,  is  free 
of  blood-vessels  and  composed  of  dense  bands  of  con- 
nective tissue.  The  above  described  mesodermic  papilla 
grows  through  an  opening  at  the  base  of  tlie  tooth  sac 
into  its  iuterior  and  forms  the  dentin-germ.  The  function 
of  the  dentin-germ  is  to  generate  the  dentin  during  devel- 
opment of  the  tooth.  When  it  is  fully  developed  it 
forms  the  dental  pulp.  On  its  surface  a  layer  of  tall  cylin- 
drical-shaped cells  are  formed,  the  odontoblasts  which  pro- 
duce dentin. 

The  formation  of  dentin  is  similar  to  that  of  bone,  the 
odontoblasts  excreting  a  protoplasmic  uncalcified  ground 
substance  which  in  turn  becomes  progressively  calcified 
from  its  periphery  toward  the  odontoblasts.  However,  a 
diffuse  calcification  of  the  whole  tissue  does  not  occur,  for 
the  dentinal  tubules  as  well  as  their  connecting  branches 
and  the  interglobular  spaces  remain  nncalcified.  The 
sheaths  of  Neumann  which  line  the  dentinal  tubules  seem 
to  possess  a  peculiar  chemical  composition  for  they  resem- 
ble neither  the  calcified  ground  substance  nor  the  organic 
dental  sul)stance,  but  are  strongly  resistive  against  all 
methods  of  decomposition  and,  therefore,  resemble  horn- 
like bodies.  The  Tomes'  fibers  are  homogeneous  proto- 
plasmic processes  which  lie  in  the  dentinal  tubules  ;  they 
represent  peripheral  elongations  of  the  bodies  of  the  odon- 
tol)lastic  cells.  Aside  from  these  enormously  long  drawn 
out  processes,  the  odontoblasts  also  possess  very  short 
lateral  offshoots  by  means  of  which  they  connect  with 
each  other.  These  branches  are  later  looked  upon  as  the 
lateral-connective  tubules  of  the  fully  developed  dentin. 
The  majority  of  the  odontoblasts  are  moreover  supplied 
with  a  third  variety  of  processes  which  are  very  short  and 
are  fastened  centrally.     The  calcification  of  the  dentinal 


86  PHYSIOLOGY. 

PLATE   II. 

Fig.  1. — Tootli-germ  of  a  young  cat.  o.  Tooth-papilla,  h.  Enamel 
pulp.  c.  Tooth-fragment,  d.  Epithelial  layer  wliicli,  according  to  von 
Brunn,  has  a  form-giving  function  in  the  formation  of  the  root.  e. 
Meckel's  cartilage.  /.  Epithelium  of  the  oral  mucosa,  g.  Bony  trabec- 
ulae  of  the  lower  jaw.      Ti.  Wall  of  the  tooth-sac.      Hematoxylin — Eosiu. 

Fig.  2. — Secondary  tooth-germ  of  a  young  cat.  «.  Tooth-papilla 
of  the  secondary  germ,  which  will  form  the  true  pulp.  6.  Milk-tooth, 
whose  roots  are  prepared  to  become  absorbed  and  to  be  forced  out.  c. 
Enamel  pulp.  d.  Eesorption  organ,  e.  Gums.  Hematoxylin — Eosin, 
with  retouche. 

Fig.  3. — A  section  of  a  human  tooth-germ  which  shows  all  the 
layers,  a.  Tooth-papilla.  6.  Odontoblasts  (Membrana  eboris).  c.  Pre- 
formative  membrane,  d.  Ameloblasts  (inner  epithelial  layer  of  the 
enamel  organ,  membrana  adamantina).  e.  Stratum  intermedium.  /. 
Gelatinous  tissue  of  the  enamel  organ,  g.  Passing  of  the  stellate  cells 
into  h,  the  outer  epithelial  layer  of  the  enamel  organ.  This  outer  epith- 
elial layer  is,  however,  not  limited  by  the  similarly  shaped  epithelial 
cells  which  are  designated  by  h,  but  stands  in  close  union  with  the  tooth- 
sac  by  means  of  ofiT-shoots  of  round  cells  which  are  penetrated  by  blood- 
vessels,    i.  Tooth-sac.     Hematoxylin — Eosin.     High  magnificatiou. 


PLATE    12. 

Tooth-fragment  from  a  deciduous  canine  tooth. — a.  Ameloblastic 
layer.  6.  Enamel  undergoing  dentification  ;  the  Tomes'  processes  of  the 
enamel  constructing  cells  are  shown,  as  well  as  the  tubes  of  the  calcified 
intercellular  substance,  which  are  superimposed  upon  each  other  in  the 
form  of  a  honey  comb.  c.  The  dentin  in  the  process  of  dentification, 
with  the  multiple  branched  terminals  of  the  Tomes'  fibers,  d.  Odonto- 
blastic layer.  Decalcified  in  hydrochloric  acid. — Alcohol.  Hematoxy- 
lin.— Eosin.     High  magnification. 

ground  substance  (dentinogene  substanz)  is  brought  about 
by  deposits  and,  therefore,  the  surface  line  between  the 
calcified  and  the  uncalcified  sub.stance  is  not  a  plain 
rounded  surface  but  is  formed  by  spherical  segments ;  for 
this  reason  the  interglobular  spaces,  which  follow  a 
momentary  disturbance  in  the  normal  process  of  calcifica- 
tion show  on  section  a  spherical  limiting  border. 

It  is  only  from  this  one  cellular  layer  that  the  whole 
dentinal  covering  arises  during  the  course  of  development. 
This  fact  had  already  been  determined  by  Koelliker,  and 
in  spite  of  many  attempts  to  weaken  this  theory  it  has 
successfully  withstood  all  attacks.  At  a  more  recent  date 
WalkhofF  corroborated  this  observation  by  means  of  care- 
fully prepared  microphotographs  of  tooth  germs. 


Tah.u. 


K^^%     -'' 


4-  CC 


Iig.l. 


Eig.2. 


Fig.3. 


Tab.l2. 


THE  DEVELOPMENT  OF  THE  TEETH.  87 

Covering  the  tooth  papilla  which  arises  from  the  floor 
of  the  tooth  germ  is  the  enamel  germ  or  enamel  organ.  It 
is  composed  of  several  different  layers  which  are  distinctly 
separated  from  one  another  (Plate  11,  Fig,  3).  The  odon- 
toblastic layer  lies  directly  upon  the  papilla  and  next  to 
it  is  the  inner  epithelial  layer  (Koelliker)  which,  analogous 
to  the  odontoblastic  layer,  is  composed  of  stratum  of  cyl- 
indrical cells,  the  ameloblasts  (enamel  constructors).  Near 
the  base  of  the  dentin  germ,  the  inner  epithelial  layer 
folds  back  outwardly  and  thus  covers  the  inner  wall  of 
the  tooth  sac  with  a  layer  of  low  epithelial  cells  (outer 
epU/iellal  layer).  The  enamel  pulp  which  is  enclosed 
between  botn  epithelial  layers  simulates  connective  tissue 
because  of  its  star-shaped  cells  whose  wide-meshed  inter- 
spaces are  filled  with  an  albumin-like  liquid.  According 
to  von  Ebner,  however,  these  cells  are  simply  altered 
epithelial  cells,  and  it  is  possible  to  trace  the  gradual  con- 
version of  the  star  cells  in  the  region  of  the  stratum  inter- 
medium, which  lies  upon  the  inner  epithelium,  into  true 
stratified  pavement  epithelium. 

Just  as  the  dentin  is  composed  of  a  single  layer  of 
specified  cells  so  is  the  whole  enamel  produced  from  a 
single  ameloblastic  layer  from  beginning  to  end.  At  first 
a  limiting  band  is  formed  on  the  enamel  constructing 
colls,  which  originally  shows  only  a  pale  cuticle-like 
border  next  to  the  young  dentin.  This  cuticle  border 
increases  in  thickness  and  thus  gradually  forces  the  amelo- 
blastic layer  away  from  the  dentin. 

The  ameloblastic  cells  are  joined  to  the  enamel,  which 
is  at  first  only  slightly  calcified,  through  their  Tomes' 
processes.  These  are  branches  from  the  cell  body  which 
become  gradually  solidified  from  within  toward  the  peri- 
phery by  deposits  of  brilliant  calcium  granules.  By  union 
of  these  calcium  granulations,  the  cell  processes  assume 
that  form  and  consistency  which  is  manifested  later  in  the 
finished  enamel  prisms. 

These  processes  are  inserted  as  may  be  seen  in  Plate 
8,  Fig.  3,  and  Plate  12,  in  hexagonal  shaped  husks 
which    taken    collectively,  on   cross  section   appear  like 


88  PHYSIOLOGY. 

a  honey-comb  ;  tliese  represent  the  modified  intercellular 
substance  which  is  preparing  for  tooth  development.  The 
shiny  processes  constantly  increase  in  thickness  and  the 
tubes  become  atrophied ;  in  the  completed  enamel  they 
exist  only  as  the  small  amount  of  interprismatic  cement 
substance. 

The  various  events  of  tooth  formation  begin  about  the 
fifth  fetal  month  and  are  ushered  in  by  the  construction 
of  a  small  hood  of  dentin  at  the  tip  of  the  tooth,  and  in 
multicuspid  teeth,  simultaneously  at  the  different  cusps ; 
to  this  hood  of  dentin  an  external  layer  of  enamel  is 
annexed  (Plate  12).  These  tooth  fragments  constantly 
increase  in  circumference  and  thickness,  while  the  addi- 
tional deposits  of  dentin  continually  decrease  the  size  of 
the  dentinal  pulp,  the  development  of  the  enamel  externally 
causes  the  enamel  pulp  to  atrophy. 

THE  DEVELOPMENT  OF  THE  ROOT. 

After  the  crown  is  developed  and  the  tooth  prepares 
for  eruption  the  construction  of  the  root  begins.  In 
this  connection,  according  to  von  Brunn,  the  enamel 
organ,  in  place  of  its  former  function  of  constructing 
enamel,  is  now  concerned  in  forming  the  root.  In  the 
neighborhood  of  the  neck  of  the  tooth  the  inner  epithelial 
layer  unites  w^ith  the  outer  epithelial  layer  so  that  the 
intermediary  layer  and  the  enamel  pulp  become  displaced. 
The  membrane  which  is  composed  of  only  two  layers  of 
epithelium  and  called  the  epithelium  membrane,  extends 
downward  in  a  tube-like  fashion  into  the  depths  of  the 
mesodermic  tissue  until  finally  a  connective-tissue  cone 
is  formed  which  has  the  length  and  form  of  the  future 
root  (See  Plate  11,   Fig.  1,  d). 

The  connective  tissue  undergoes  alteration  into  typical 
pulp  tissue,  on  the  periphery  of  which  lie  odontoblasts, 
exactly  as  was  described  in  connection  with  the  primitive 
tooth  papilla.  Later  the  epithelial  layer  becomes  absorbed, 
a  small  portion  of  it,  however,  remains  in  the  form  of  the 
before  mentioned  epithelial  nests  in  the  periosteum  of  the 


CALCIFICATION  OF  THE  DECIDUOUS  TEETH.      89 

root.  The  odontoblasts  which  are  developed  in  the  newly- 
formed  epithelial  layer  furnish  the  dentin  for  the  root.  As 
soon  as  some  of  the  dentin  is  deposited,  the  cementum  of  the 
roots  begins  to  form.  This  is  brought 
about  by  cells  being  detached  from  the 
inner  wall  of  the  tooth  sac,  which  become 
the  osteoblasts.  They  wander  through  the 
epithelial  layer  and  attach  themselves  to 
the  surface  of  the  dentin  and  at  first  gen- 
erate upon  the  same  only  a  thin  coat  of  ce- 
mentum, which  gradually  becomes  thicker.  5,^^  43._Lower 
Fig.  43  gives  amacroscopical  representation  fre^'^nit'^'ef  com^ 
of  the  process  of  root  development  in  an  pieteiy  developed. 
uncompleted  molar. 

At  the  time  of  root  development  the  tooth  sac  is  grown 
fast  at  its  crown  with  the  gum.  During  the  period  of 
tooth  eruption  the  summit  of  the  tooth  sac  remains  intact, 
and  is  the  first  part  to  penetrate  the  gum  and  enter  the 
oral  cavity.  Then  this  covering  is  pierced  by  the  upward 
growth  of  other  teeth,  and  falls  back  around  the  neck  of 
the  tooth,  where  it  grows  fast  to  the  gums  and  forms  the 
circular  liyament.  The  remaining  portion  of  the  tooth 
sac  is  hemmed  in  between  the  alveolus  and  the  tooth  root, 
where  it  forms  a  union  between  the  two,  and  in  the  course 
of  time  becomes  the  alveolar  periosteum. 

The  mechanism  concerned  in  the  eruption  of  teeth  is  not 
yet  fully  understood.  It  seems  that  a  number  of  factors 
are  combined  in  this  process ;  these  include  longitudinal 
growth  of  the  roots,  proliferation  of  the  cells  of  the  pulp 
eminence,  and  phenomena  of  growth  in  the  surrounding 
tissues. 


CALCinCATION  OF  THE  DECIDUOUS  TEETH. 

Calcification  of  the  deciduous  teeth  occurs  in  the  order 
in  which  they  come  to  eruption.  Hence  the  incisors  first 
become  calcified  and  the  molars  not  until  later.  The 
ages  at  which  the  primary  teeth  become  calcified  are 
graphically  demonstrated  in  the  upper  illustration  of  Fig. 


90  PHYSIOLOGY. 

47,  which  is  reproduced  from  the  copy  of  Pierce,  in 
"  Amoedo's  Legal  Dentistry."  The  records  of  this  table 
do  not  agree  absolutely  with  those  of  other  authors.  This 
is  probably  due  to  the  fact  that  variations  in  the  process 
of  calcification  are  as  frequent  as  they  are  in  the  time  of 
eruption.  According  to  Pierce  the  calcification  begins  in 
the  17th  fetal  week,  exactly  at  the  period  when  the  back 
part  of  the  tooth  band  begins  to  undergo  the  invagination 
process  for  the  permanent  molars.  At  birth,  the  crowns 
of  the  incisor  and  cuspid  teeth  are  almost  completed,  while 
only  two-thirds  of  the  crowns  of  the  molars  are  developed. 
Complete  development  of  the  roots  does  not  occur  until 
between  the  eighth  and  twenty-second  month  after  birth. 
As  has  already  been  mentioned,  the  calcified  part  of  the  tooth 
is  called  in  the  early  stage,  the  tooth  fragment.  This  is 
composed  of  a  deposit  of  dentin  and  enamel,  Mhich  lies 
like  a  hood  upon  the  tooth  papilla.  The  uplifting  of  the 
dentin  begins,  according  to  Rose,  simultaneously  with  that 
of  the  enamel.  The  tooth  fragment  Avhich  is  thin  at  the 
beginning,  gradually  becomes  larger  through  a  constant 
growth  in  thickness  both  at  the  hood  and  at  the  sides. 

ERUPTION  OF  THE  DECIDUOUS  TEETH. 

It  is  of  importance  in  the  practice  of  dentistry  to  know 
exactly  the  time  at  which  the  first  teeth  erupt,  for  each 
tooth  eruption  is  the  cause  of  much  worry  to  the  anxious 
mother.  As  disturbances  in  the  general  health  of  tlie 
infant  are  not  infrequently  associated  with  the  eruption 
of  a  tooth,  a  certain  amount  of  anxiety  is  justified. 

The  normal  period  of  eruption  for  the  central  incisors 
of  the  lower  jaw  is  about  the  sixth  month,  while  that  of 
the  same  teeth  of  the  upper  jaw  is  a  little  later.  During 
the  eighth  month  the  upper  lateral  incisors  reach  the 
eruptive  stage,  being  closely  followed  by  the  lower  lateral 
incisors.  The  first  molars  of  the  lower  jaw  appear  about 
the  twelfth  month,  while  those  of  the  upper  jaw  erupt  a 
little  later.  The  cuspid  teeth  come  to  eruption  in  the 
sixteenth  month,  and  finally,  the  second  molars  complete 


ERUPTION  OF  THE  TEETH.  91 

the  row  of  deciduous  teeth  at  about  the  twentieth  month. 
These  dates,  however,  do  not  always  hold  true.  Ca.ses 
are  reported  in  which  the  fetus  was  already  provided  at 
birth  with  a  complete  dental  apparatus.  On  the  other 
hand,  the  eruption  is  sometimes  much  delayed,  so  much 
so  that  even  in  the  second  and  third  years  of  life  no  tooth 
has  made  its  appearance.  This  may  occur  in  perfectly 
healthy  children  ;  often,  however,  the  cause  is  attributable 
to  some  form  of  disease,  such  as  syphilis,  scrofula,  and 
perhaps  also  rachitis.  Also  the  teeth  of  poorly  nourished 
children  are  frequently  later  in  eruption  than  those  of  well 
cared  for  children.  For  our  country  the  following  periods 
of  eruption  of  the  deciduous  teeth  may  be  accepted  as 
being  normal : 

Central  incisoi'S    . =    .    6  to    8th  month. 

Lateral  incisors 8  to  12th      " 

First  molai-s 12  to  16th      " 

Cuspid 16  to  20th      " 

Second  molars 20  to  30th      " 


6-Sth  month 

8-12lh  month 

16-20th  month 

12-16th  month 
'20-SOth  month 


Fig.  44.— Dates  of  eruption  of  the  deciduous  teeth. 

For  the  better  understanding  of  the  subject  I  have  pre- 
sented in  Fig.  44  a  diagram  of  the  deciduous  teeth  with 
dates  of  eruption. 

DISTURBANCES   ACCOMPANYING    ERUPTION  OF  THE 

TEETH. 

A  certain  amount  of  pain  in  connection  with  eruption 
of  the  teeth  seems  to  be  physiological.  Rarely  does 
eruption  of  the  incisors  lead  to  important  disturbances. 


92  PHYSIOLOGY. 

The  molars,  however,  are  more  likely  to  cause  trouble 
while  the  cuspid  teeth  too  are  not  altogether  innocent  in 
this  respect.  The  intensity  of  the  child's  suifering  is  not 
always  in  proportion  to  the  pain ;  sensitive  children  often 
cry  furiously  during  a  perfectly  easy  period  of  eruption, 
while  children  of  a  less  sensitive  nature  make  no  outcry 
whatever  even  though  disturbances  of  eruption  are  present. 
Hence  it  is  a  difficult  matter  to  decide  in  the  different 
cases  between  physiologic  and  pathologic  eruptions.  It 
has  been  attempted  to  avoid  this  dilemma  by  simply  con- 
sidering an  eruption  a  difficult  one  when  symptoms  of  dis- 
turbances in  the  general  health  of  the  infant  accompany  it. 

The  following  three  different  forms  of  disturbances 
accompanying  eruption  of  the  deciduous  teeth  are  recog- 
nized : 

Infantile  Odontalgia. — This  is  due  to  the  toughness 
of  the  gum  which  offers  great  resistance  t©  the  erupting 
tooth.  Pressure  is  thus  caused  upon  the  still  exposed 
dental  pulp  and  therefore  the  child  suffers  toothache  even 
before  the  tooth  has  penetrated  the  gums.  In  such  cases 
the  gum  itself  is  not  involved,  that  is,  it  is  neither  red  nor 
swollen,  but  it  is  anemic  and  tightly  strung  over  the  sum- 
mit of  the  tooth's  crown.  The  pains  are  especially  severe 
when  an  attempt  is  made  to  suckle,  this  is  recognized  -by 
the  fact  that  the  child  cries  furiously  as  soon  as  it  is 
placed  at  the  mother's  breast.  Under  these  conditions 
too,  a  mild  form  of  constipation  nearly  always  exists. 

The  treatment  should  be  expectant,  that  is,  postpone 
treatment  and  watch  wdiether  the  tooth  will  appear  in  the 
mouth  without  interference.  As  soon  as  this  occurs  all 
pain  disappears.  If,  however,  the  symptoms  of  general 
disturbance  become  pronounced  it  is  advisable  to  relieve 
the  condition  by  making  a  deep  incision  through  the 
tightly  stretched  gum.  Before  the  incision,  as  well  as 
afterwards,  and  especially  after  meals,  the  child's  mouth 
should  be  carefully  swabbed  out  with  clean  cotton  soaked 
in  a  20  per  cent,  solution  of  boric  acid.  To  combat  the 
constipation  the  following  is  prescribed  : 


ERUPTION  OF  THE  TEETH.  93 

R  Inf.  sennae  comp. 

SjTup.  mannse  aa        fjj  (30.0). 

M.  et  Sig.    One  tablespoonful  hourly  until  a  bowel  movement 
follows. 

Infantile  Odontitis. — In  this  type  of  difficult  tooth 
eruption  contrary  to  the  preceding  form,  symptoms  refer- 
able to  the  gums  are  the  most  prominent.  In  infantile 
odontitis  the  pain  is  not  caused  by  the  compressed  dental 
pulp  but  by  the  condition  of  the  gum.  This  structure  is 
primarily  inflamed  at  the  seat  of  eruption,  later,  however, 
the  inflammatory  process  spreads  to  the  surrounding  tissue 
so  that  finally  a  large  area  becomes  involved  and  highly 
sensitive.  The  affected  region  is  reddened,  swollen  and 
not  infrequently  covered  with  ulcers.  The  inflammation 
may  also  extend  inwardly  and  lead  to  a  periostitis  and 
osteitis  of  the  jaw. 

Symptoms  attributable  to  constitutional  disturbances  are 
usually  less  severe  than  in  odontalgia.  Disturbances  in 
alimentation  nearly  always  accompany  infantile  odon- 
titis. A  considerable  increase  in  local  temperature  exists 
in  the  neighborhood  of  the  cheeks,  and  saliva  flows  freely 
from  the  mouth. 

Treatment  is  not  always  necessary  since  like  in  odon- 
talgia, the  disease  process  often  ceases  when  the  tooth  has 
erupted.  Under  no  circumstances  should  the  gum  be 
incised,  for  such  a  procedure  may  easily  result  in  sepsis 
of  the  irritated  mucous  membrane.^  It  is  better  to  try  to 
lessen  the  inflammation  with  a  mild  antiseptic  solution. 
A  favorite  mixture  is  the  following: : 

R  Boracis  .^j  (4.0). 

Aquae  rosati  f^j  (30.0). 

M.  et  Sig.     For  painting  the  gums. 

['This  is  not  in  accord  witli  dental  teaching  in  America.  Accumu- 
lated clinical  experience  demonstrates  that  when  this  form  of  irritation 
becomes  pronounced,  the  mouth  becomes  hot  and  drj' — the  secretions 
having  become  checked,  ulcerations  appear  upon  the  mucous  membrane 
of  the  mouth,  eruptions  upon  the  face  and  scalp,  in  fiict  sometimes  over 
the  whole  body,  and,  if  prompt  relief  is  not  given  \i\  free  Inncinq  of  the 
gums,  the  child  may  h)se  his  appetite,  suffer  from  nausea,  diarrhoea,  or 
even  convulsions.  The  free  use  of  the  lancet  and  even  cutting  off  sections 
of  gum-tissue  over  molars,  in  some  cases,  may  save  the  child  a  serious 
illness. — Ed.] 


94  PHYSIOLOGY. 

Convulsions. — These  result  during  the  eruption  of 
teeth  because  of  the  increased  nervous  irritability  of  the 
child.  They  are  reflex  in  nature  and  may  therefore  occur 
independently  or  associated  with  other  disturbances  of 
difficult  dentition.  The  spasms  are  clonic  and  tonic  in 
character  which  either  involve  individual  muscle  groups 
or  spread  over  the  whole  body. 

That  these  convulsions  are  associated  with  dentition  is 
recognized  by  nearly  every  layman.  According  to  Baume 
it  has  not  been  scientifically  proven  that  such  attacks  are 
always  due  to  the  difficult  eruption  of  teeth,  for  during 
this  period  the  brain  and  spinal  cord  undergo  important 
developmental  changes  so  that  it  is  quite  possible  that  any 
interference  with  health  may  result  in  spasmodic  seizures 
of  the  muscles.  Therefore  in  order  to  establish  the 
etiology  it  is  necessary  to  inspect  the  oral  cavity  in  such 
cases.  If  the  inflammation  is  found  to  be  present  with 
marked  sensitiveness  of  the  area  covering  the  tooth's 
crown  it  is  safe  to  consider  that  process  the  cause  of  the 
convulsions. 

The  therapy  of  these  convulsions,  sometimes  termed 
tooth  cramps,  is  often  quite  u.seless.  If  an  odontalgia 
accompanies  them  an  incision  in  the  most  tense  portion 
of  the  gum  may  give  relief,  also  an  associated  odontitis 
must  be  specifically  treated.  If  these  complications  are 
absent  the  treatment  must  be  symptomatic,  which,  consists 
in  treating  the  irritated  nerve  by  local  applications  of  a 
narcotic.    For  this  purpose  the  following  is  recommended  : 

R  Spiritis  vini  f^ijss  (10.0). 

Chloroformi  f^ss  (2.0). 

M.  et  Sig.     Eub  as  a  liniment  into  the  gum  and  cheek. 

THE  RESORPTION  OF  THE  DECIDUOUS  TEETH. 

The  last  of  the  primary  teeth  have  hardly  made  their 
appearance  in  the  mouth  before  the  resorption  process 
commences  in  the  incisors.  This  consists  first  in  exertion 
of  pressure  upon  the  deciduous  by  the  permanent  crowns, 
which  by  this  time  have  become  more  calcified.    Undoubt- 


RESORPTION-  OF  DECIDUOUS  TEETH.  95 

edly  the  developing  permanent  teeth  are  the  first  factors 
concerned  in  bringing  about  this  change.  An  argument 
in  behalf  of  this  theory  is  the  observation  made  quite 
frequently,  that  in  certain  situations  where  the  permanent 
teeth  fail  to  erupt,  the  corresponding  deciduous  teeth  are 
not  lost.  They  retain  their  healthy  root, 
remain  viable,  and  stand  in  the  row  of 
permanent  teeth  until  extreme  old  age. 
Another  feature  which  speaks  favorable  for 
this  supposition  is  the  fact  that  the  portions 
of  the  root  wear  away  which  are  pressed  tra/an'd'a~iaterai 
upon  bv  the  crowns  of  the  permanent  teeth. ^    deciduous    inci- 

L        ''     T  -i->  1   TT^     11    ii  sor  tooth    show- 

Accordmg  to  iiaume  and  W  eui  the  re-  ing  partial  ab- 
sorption process  includes  the  bone  marrow  roots.^*^"  ^  *  ^ 
as  well  as  the  periosteum  of  the  milk 
teeth,  von  Metnitz  also  believes  that  this  process 
is  shared  by  the  periosteum  but  he  is  not  convinced 
of  any  active  change  in  the  bone  marrow.  Waldeyer 
informs  us  of  a  proliferation  of  the  milk  tooth  sac,  by 
which,  however,  he  evidently  means  the  root  periosteum 
of  the  deciduous  teeth,  for  at  the  time  of  the  resorption 
process  the  primary  tooth  sac  has  disappeared.  Robin 
advocates  an  altogether  different  theory  in  which  he 
ascribes  to  the  follicular  sac  of  the  permanent  teeth  a 
resorptive  action  upon  the  surrounding  tissues,  including 
the  alveoli  and  the  roots  of  the  first  teeth. 

von  Metnitz  who  has  given  this  subject  a  close  study, 
made  the  observation  that  in  freshly  extracted  deciduous 
teeth,  which  were  undergoing  absorption  tlie  cavity  caused 
by  the  absorption  process  presented  a  soft  red  tissue, 
which  even  with  the  naked  eye  could  be  seen  to  consist 
of  proliferative  granulations. 

If  this  granulated  tissue  is  forcibly  removed  a  rough 

['  The  position  taken  by  the  author  regardinof  the  cause  of  the  resorp- 
tion process  known  as  decalcification  of  the  teeth,  is  not  altogether  in 
accord  with  the  accepted  theories  of  American  dental  teachers.  It  is  not 
now  generally  regarded  that  the  presence  and  advance  of  the  perma- 
nent teeth  plays  any  part  in  this  interesting  action.  In  other  words,  it 
is  conceded  that  it  is  simply  a  physiological  action  and  not  the  result  of 
a  mechanical  force. — Ed.] 


96 


PBYSIOLOGY. 


surface  is  exposed,  which  is  comprised  of  numerous  fine 
recesses  which  are  surrounded  by  little  pointed  pro- 
jections of  varying  length.     Under  the  microscope  these 

recesses  show  a  close  resem- 
blance to  the  Howship's  lacunae 
which  accompany  a  rarefying 
osteitis.  They  are  filled  with 
giant  cells,  the  majority  of 
which  contain  multiple  nuclei. 
With  reference  to  their  func- 
tion Koelliker  calls  them  oste- 
oclasts ( Fig.  46,  6 ).  Numerous 
blood  vessels  and,  to  which  von 
Metnitz  called  especial  atten- 
tion, long  bands  of  newly 
formed  connective-tissue  fibrils 
pass  between  the  osteoclasts. 
These  fibrils  may  be  traced 
through  the  pores  of  the  bony 
alveolus  into  the  bonemarrow. 
In  many  areas  the  defects  fol- 
lowing absorption  are  filled 
with  cement  which,  however, 
already  present  absorption  lacunae  of  varying  size  and  which 
in  the  course  of  this  process  again  undergo  complete  dissolu- 
tion. The  interrupted  absorption  process  then  begins  anew. 
I  believe  that  this  depends  upon  the  activity  of  the  perios- 
teum, which  up  to  this  time  remained  almost  intact.  Only 
after  some  time  does  the  root  periosteum  change  into  granu- 
lation tissue,  after  which  the  process  in  the  cementum 
proceeds  more  vigorously.  The  dentin  is  affected  more 
rapidly  but  here  too  no  smooth  absorption  surfaces  develop 
but  the  border  line  of  the  abrated  area  has,  on  longitudi- 
nal section,  the  form  of  joined  segments,  similar  to  the 
calcification  border  of  the  dentin.  After  the  greater 
portion  of  the  root  has  been  destroyed,  the  pulp  of  the 
milk  tooth  becomes  exposed.  Its  elements  degenerate 
completely  and  the  afferent  blood  vessels  become  con- 
stricted.    But  if  by  chance  vascular  connection  is  main- 


FiG.  46.— A  deciduous  root 
undergoing  absorption,  a.  Den- 
tin with  absorption  lacunae,  b. 
Osteoclasts,  c.  Connective  tissue 
cells.  Hydrochloric  acid. — Alco- 
hol.— Decalcification. 


RESORPTION  OF  DECIDUOUS  TEETH.  97 

tained  after  the  dentin  surrounding  the  pulp  has  been 
lost,  then  osteoclasts  may  develop  in  the  tissue  of  the  pulp 
which  bestow  upon  it  the  function  of  an  absorptive  organ. 

The  various  authors  do  not  agree  as  to  the  more  minute 
changes  in  the  absorptive  process  of  the  hard  tooth  sub- 
stances. Baume  believes  that  the  blood  plasma  acts  as  a 
chemical  agent  and  states  that  "It  is  plain  to  see  that  the 
blood  plasma  which  circulates  about  the  resorption  sur- 
face dissolves  and  carries  off  the  hard  tooth  substances. 
The  blood  plasma  has,  as  is  known,  the  power  to  hold  in 
solution  before  depositing  them,  calcium  salts  which  are 
needed  for  the  upbuilding  of  the  bones  and  teeth.  A 
chemical  body  which  holds  a  substance  in  solution  can, 
under  certain  circumstances  absorb  it.  These  conditions 
develop  as  soon  as  the  tooth  loses  its  life.  The  granu- 
lations are  therefore  the  indirect  cause  and  perhaps  also 
primarily  the  result  of  the  loss  of  the  tooth  substance." 

Tillmann  assumes  that  the  osteoclasts  are  capable  of 
excreting  carbonic  acid  which  dissolves  the  calcium  salts, 
and  that  the  organic  residue  is  then  assimilated  by  the 
osteoclasts.  Schaffer  also  considers  carbonic  acid  as  the 
absorbing  agent  and  according  to  him  this  gas  is  filtered 
through  the  venous  capillaries  by  means  of  the  osteo- 
clasts. 

Resorption  lacunae  may  also  result  by  mechanical 
means  and  indeed  they  may  be  due  to  ameboid  move- 
ments, as  is  believed  by  Wedl,  but  the  possibility  has  not 
been  excluded  that  these  processes  go  hand  in  hand  with 
excretion  of  the  substances  which  dissolve  lime  salts. 

If  in  conclusion  the  changes  in  the  absorption  of  the 
human  teeth  are  again  studied  it  will  be  concluded  accord- 
ing to  the  author's  observation  that  the  phenomena 
observed  are  wholly  analogous  to  those  which  occur  in 
the  physiologic  bone  absorption,  as  determined  by  von 
Koelliker  (in  development  of  bone).  As  we  know,  he 
advanced  the  proposition  that  bone  development  from  a 
periosteal  as  well  as  an  endochondral  and  a  membranous 
base,  consists  in  the  apposition  of  bone  on  the  one  side, 
and  the  absorption  of  bone  on  the  other  side,  the  processes 
7 


98  PHYSIOLOGY. 

FIGURE  47. 

Upper  Illustration.  A  graphic  presentation  of  the  dates  of  calcification 
of  the  milk  teeth. 

Lower  illustration.  A  graphic  presentation  of  the  dates  of  calcification 
of  the  permanent  teeth. 

alternating  with  each  other.  Through  the  apposition  of 
bone  elements  the  bone  derives  its  thickness,  width  and 
length,  and  through  absorption  it  loses  its  form  externally 
while  internally  the  various  spaces  are  constructed,  von 
Koelliker  determined  in  his  investigations  that  this 
absorption  process  is  brought  about  by  large  multi-nucle- 
ated cells,  the  above  mentioned  osteoclasts,  which  vary 
considerably  in  shape.  Tomes  had  already  observed 
these  giant  cells  in  the  absorption  of  the  tooth  roots  and 
the  question  of  the  origin  arose  in  his  mind. 

According  to  the  observation  of  Virchow  and  Rind- 
fleisch  such  osteoclasts  arise  from  a  body  in  the  living 
bone,  and  Kassowitz  also  considers  them  as  a  residue 
from  the  bony  tissue.  Arguments  against  this  theory  are 
the  resorption  processes  in  the  deciduous  roots  and  in  the 
artificially  implanted  ivory  pegs.  In  reference  to  the 
latter,  Tillraann  stated  that  resorption  fossse  occur  in  such 
artificial  pegs  similar  to  those  of  living  bone.  This  fact 
plainly  indicates  that  the  agent  concerned  must  be 
looked  for  elsewhere  than  in  the  bone.  Some  authors, 
among  them  Schwalbe,  Wegener,  and  Pommer  are  of  the 
belief  that  the  osteoclasts  may  arise  from  osteoblasts  as 
well  as  other  cells,  while  von  Koelliker  considers  them 
as  being  modified  ordinary  connective-tissue  bodies. 
Wegener's  decision  that  the  osteoclasts  originate  in  the 
cells  of  the  adventitia  of  the  blood  vessel  walls  does  not 
argue  against  that  conclusion,  for  these  elements  signify 
nothing  more  than  connective-tissue  cells. 

Therefore  osteoclasts  may  arise  from  all  the  different 
varieties  of  cells  which  occur  in  the  connective-tissue  sub- 
stance surrounding  the  roots  of  the  deciduous  teeth,  and 
are  the  direct  cause  of  absorption.  This  does  not,  how- 
ever, exclude  the  fact  that,  like  the  absorptive  processes 
in  normal  bone  development  so  also  in  this  connection, 


22nd  month  after  birth 
18th  month  after  birth 
12th  month  after  birth 


6th  month  after  birth — ■ 

At  time  of  birth 
30th  week  (fetus t 
18th  week  (fetus I 
17th  week  (fetus,) 


12th  year 
10th  year 
9th  year 


20th  year 
18th  year 
16th  year 


Fig.  47. 


ERUPTION  OF  THE  PERMANENT  TEETH.         99 

the  osteoblasts  may  be  transformed  into  osteoclasts.  At 
any  rate,  sufficient  numbers  of  osteoblasts  exist  in  the 
resorption  lacunae  on  account  of  the  before  described 
apposition  of  newly  formed  bone. 

CALCIFICATION  OF  THE  PERMANENT  TEETH. 

The  crown  of  the  first  molar  begins  development  at  the 
time  of  birth,  as  is  shown  in  the  lower  illustration  of 
Fig.  47.  Calcification  of  the  crowns  of  the  incisors  begins 
during  the  second  year  of  life,  and  that  of  the  crowns  of 
the  cuspid  teeth  during  the  third  year.  In  the  fifth  year 
of  age  the  cusps  for  the  second  molars  develop  and  those 
for  the  third  molars  in  the  ninth  year.  With  the  excep- 
tion of  the  wisdom  teeth  calcification  of  the  crowns  ceases 
about  the  ninth  year,  but  at  this  time  the  roots  are  not  yet 
completely  calcified.  Calcification  of  the  roots  of  all  the 
teeth  is  not  completed  until  between  the  twelfth  and 
eighteenth  year. 

A  full  knowledge  of  the  periods  of  calcification  is  of 
considerable  practical  value.  It  is  well  known  that  dis- 
turbances in  health  of  any  kind  influence  the  teeth,  and 
may  cause  defective  calcification  of  the  tooth  tissue.  Such 
disturbances  in  health  occur  naturally  more  frequently 
during  the  earlv  years  of  existence  than  later  in  life, 
therefore  we  find  frail,  poorly  calcified  molar  and  incisor 
teeth  more  frequently  than  similar  conditions  in  the  other 
groups  of  teeth.  Cases  are  not  infrequently  met  with  in 
practice  which  show  defective  development  of  the  enamel 
{hypoplasia)  only  in  the  incisors,  while  the  remaining  teeth 
are  covered  with  beautiful  glossy  enamel.  In  these  cases 
we  are  usually  able  to  trace  the  cause  of  the  phenomena 
to  some  disease  existing  during  the  first  years  of  life. 

ERUPTION  OF  THE  PERMANENT  TEETH. 

The  dentist  is  consulted  more  frequently  in  eruption  of 
the  permanent  teeth  than  in  that  of  the  deciduous  set,  for 
disturbances  in  normal  tooth  substitution  are  very  fre- 
quent for  various  reasons.     About  the  sixth  year  the  first 


100 


PHYSIOLOGY. 


FIGURE   49. 

Position  of  the  permanent  tooth  crowns  before  absorption  of  the 
deciduous  roots. 


permanent  molars  of  the  lower  jaw  appear  in  the  mouth, 
and  are  followed  soon  after  by  the  eruption  of  those  of  the 
upper  jaw.  The  central  incisors  erupt  in  the  seventh  year, 
and  the  lateral  incisors  in  the  eighth  year ;  and  as  is  true 
of  the  molars,  those  of  the  lower  jaw  appear  first.  Begin- 
ning with  the  ninth  year  the  first  bicuspids  appear,  and 
the  upper  are  usually  the  first  to  make  their  appearance. 
In  the  tenth  year  they  are  followed  by  the  second  bicus- 
pids, and  about  the  eleventh  year  by  the  cuspid  teeth. 


6-9th  year 


7-lOth  year 
i  «^9-14tli  year 


10-14th  vear 


16-40th  year 


Fig.  48.— Periods  of  eruption  of  the  permanent  teeth. 

In  the  twelfth  year  the  second  molars,  and  between  the 
eighteenth  and  the  twenty-fifth  years  the  third  molar  or 
so-called  wisdom  teeth  appear.  The  dates  are  subject  to 
various  influences,  according  to  circumstances,  such  as  the 
condition  of  the  general  health,  the  nourishment,  race,  etc. 
In  order  to  indicate  the  limits  within  which  the  normal 
periods  of  eruption  vary,  the  data  given  by  Berten  are 
reproduced  below : 


Fig.  49. 


LOCATION  OF  THE  PERMANENT  CROWNS.     101 

Eruption  of  the  first  molars  occurs  between  the  5-  8  year. 

"  "  middle  incisors     "  "  "  6-  9  year. 

"  "  lateral  incisors      "  "  "  7-10  year. 

"  "  first  bicuspids       "  "  "  9-13  year. 

"  "  cuspid  teeth          "  "  "  9-14  year. 

"  "  second  bicuspids  "  "  "  10-14  year. 

"  "  second  molai-s       "  "  "  10-14  year. 

"  "  third  molars         "  "  "  16-40  year. 

Ill  Fig.  48  we  present  a  diagram  of  the  permanent  set 
of  teeth  with  the  dates  of  eruption  appended. 


LOCATION  OF  THE  PERMANENT  CROWNS  BEFORE  THE 
ABSORPTION  OF  THE  DECIDUOUS  TEETH  ROOTS. 

By  studying  the  maxillary  preparations  of  children 
from  four  to  seven  years  of  age,  in  which  the  outer  alve- 
olar plate,  both  of  the  upper  and  of  the  lower  jaw,  has 
been  chiseled  away,  considerable  information  may  be 
obtained  regarding  the  process  accompanying  the  substitu- 
tion of  the  deciduous  by  tlie  permanent  teeth.  Such  a 
preparation  is  presented  in  Fig.  49.  The  most  prominent 
feature  observed  is  the  position  of  the  permanent  teeth, 
which  lie  below  and  back  of  the  first  teeth,  and  it  is 
further  noted  that  the  permanent  incisors  lie  on  the  lin- 
gual aspect,  back  of  the  deciduous  incisor  and  cuspid 
teeth.  The  permanent  molars  are  placed  directly  under 
and  also  somewhat  to  the  lingual  side  of  the  deciduous 
molars.  The  broad  crowns  of  the  permanent  teeth  have 
hardly  sufficient  room  in  the  young  jaw,  and  therefore 
slide  over  each  other  like  the  tiling  of  a  roof.  The  excep- 
tionally large  cuspid  teeth  lie  in  a  high  position  in  the 
neighborhood  of  the  infraorbital  foramen.  Later  when 
this  tooth  makes  its  appearance  in  the  mouth  its  position 
again  attracts  attention,  for  the  point  at  which  it  pierces 
the  alveolar  process  is  much  higher  than  in  the  case  of  all 
the  other  teeth. 

We  are  often  consulted  on  account  of  the  high  position 
at  which  the  upper  cuspid  appears  in  the  alveolar  process, 
and  the  patient  is  nearly  always  astonished  to  hear  that  it 
is  a  normal  condition.     The  same  is  true  of  the  lower  per- 


102  BACTERIOLOGY. 

manent  incisors,  which  break  forth  back  of  the  deciduous 
incisor  teeth,  a  relationship  which  is  shown  in  Figs.  49 
and  50.     In  Fig.  50  a  child's  inferior  roaxilla  is  presented, 


Fig.  50. — Deciduous  alveoli  and  alveoli  for  the  permanent  front  teeth. 

from  which  the  six  front  teeth  have  been  extracted  in 
order  to  show  the  alveoli  for  the  permanent  front  teeth 
which  lie  back  of  the  deciduous  alveoli. 


BACTERIOLOGY. 

Since  the  mouth  offers  a  place  of  abode  for  the  develop- 
ment of  an  endless  number  of  micro-organisms,  we  are 
hot  only  justified,  but  also  obliged  from  point  of  duty,  to 
discuss  to  a  certain  extent  the  bacteriology  of  the  oral 
cavitv.  The  existing  conditions  are  especially  favorable 
for  the  propagation  of  micro-organisms,  in  as  much  as  the 
mouth  offers  moisture  and  nutritive  material  in  sufficient 
quantities  at  a  satisfactory  temperature. 

Circumstances  are  more  favorable  for  the  entrance  of 
micro-organisms  into  the  mouth  than  perhaps  in  any  other 
human  organ.  AVith  each  inspiration  through  the  open 
mouth,  bacteria  or  other  spores  are  deposited  on  the  sticky 
surface  of  the  mucous  membrane.  Aside  from  the  air 
germs  a  large  number  of  heterogeneous  organisms  are 
transported  into  the  mouth  through  food  and  drink,  and 
by  means  of  various  objects  which  are  carried  into,  or  to 
the  mouth,  such  as  cigars,  tooth  picks,  postage  stamps, 
envelopes,  and  even  dental  and  surgical  instruments,  etc. 


MORPHOLOGY  AND  BIOLOGY.  103 

By  these  various  agents  infection  may  be  carried  into  the 
mouth  from  without. 

The  body  itself  may  produce  the  germs,  a  possibility 
which  must  not  be  forgotten,  for  occasionally  it  may  be  of 
assistance  in  establishing  a  diagnosis.  This  is  true,  for 
instance,  in  pulmonary  tuberculosis,  one  of  the  most  fre- 
quent signs  of  which  is  the  infected  condition  of  the 
mouth.  In  this  case  the  bacilli  reach  the  oral  cavity, 
either  through  ciliated  movements  or  by  coughing,  and  are 
found  in  the  mucous  of  the  mouth  or  in  the  expectoration. 
In  a  similar  manner,  bacteria  which  have  developed  in 
the  stomach  occasionally  may  be  carried  up  through  hic- 
cough or  vomiting. 

In  conclusion,  heraatogenetic  infection  infrequently  con- 
sists in  the  entrance  of  bacteria  into  the  circulation  through 
erosion  of  the  walls  of  the  blood-vessels  and  their  trans- 
mission to  distant  organs.  Such  an  infection  may  occur, 
for  example,  in  phthisis  and  in  white  tumor  of  the  knee. 

MORPHOLOGY  AND  BIOLOGY. 

We  will  refer  here  to  the  morphology  and  biology  of 
the  schizomycetes,  and  for  this  purpose  use  the  modern  and 
classic  treatise  of  the  subject,  as  presented  by  Lehmanri 
and  Neumann.  (Published  by  J.  F.  Lehmann,  Miinchen, 
1899).  The  term  schizomycetes  represents  small  organ- 
isms measuring  from  2-5  m.  in  width,  which  are  free  of 
chlorophyll,  unbranched  and  multiply  by  cell  division  in 
a  vegetative  manner.  They  are  usually  looked  upon  as 
belonging  to  the  vegetable  kingdom,  for  up  to  the  present 
time  they  have  not  been  found  to  possess  any  other  organ 
than  the  motion-giving  cilise.  That  this  is  altogether 
true  has  not  yet  been  proved,  for  a  number  of  the  elements 
in  this  class  have  a  marked  similarity  to  the  flagellates 
which  belong  to  the  animal  kingdom. 

On  account  of  their  minute  size  no  satisfactory  investi- 
gation of  them  has  been  accomplished.  This  is  especially 
true  of  their  mode  of  propagation.  Whether  all  micro- 
organisms may  be  included  under  the  title  of  bacteria  is 


104  BACTERIOLOGY. 

most    doubtful,    for   the   various   micro-organisms    show 
extraordinary  diiferences  from  a  biologic  standpoint. 

•  •  « 
•  •  • 

a 


d^  e 


•a* 


/ 

Fig.  51. — a,  cocci ;  &,  diplococci ;  c,  streptococci ;  d,  staphylococci ;   e,  tetrads ; 
/,  sarciuEe;  g,  bacilli;  h,  streptobacilli ;  z,  vibriones;  k,  spirilla. 

According  to  their  form  the  schizomycetes  are  divided 
into  the  following  groups  : 

1.  Cocci  which  are  bullet-shaped   spheric   cells.     The 
small  ones  are  micrococci ;  the  large  ones  macrococci. 

2.  Bacteria  wdiich  are  short  rods. 

3.  Bacilli  which  are  long  rods. 

4.  Leptothrix  which  are  thread-like  in  shape. 

5.  Vibriones  which  are  spiral  or  comma-shaped  bac- 
teria. 

6.  Spirilla  which  have  a  long  spiral  form. 
According  to  their  grouping  in  growth,  the  schizomy- 
cetes are  classified  as  follows  : 

1.  Diplococci — micrococci  occurring  in  pairs. 

2.  Streptococci — a  chain  of  micrococci. 

3.  Staphylococci — grouped  like  a  bunch  of  grapes. 

4.  Tetrads — plate-like  clusters  of  four,  eight,  or  sixteen 
micrococci. 

5.  Sarcinse — forming  packet-like  groups  of  eight-celled 
cubes. 

6.  Diplococci — bacilli  in  pairs. 

7.  Streptobacilli — a  chain  of  bacilli. 

We  are  especially  interested  in  the  chemical  action  of 


MORPHOLOGY  AND  BIOLOGY.  105 

the  bacteria.  This  activity  occurs  in  mauy  ways  for  the 
production  of  chemical  substances  which  make  the  culture 
medium  on  which  they  thrive  more  assimilable.  Such 
substances  are  called  bacterial  ferments.  They  also  gen- 
erate real  metabolic  substances  ;  that  is,  they  excrete  chem- 
ical bodies  that  are  entirely  different  from  those  which 
they  assimilate  from  their  surroundings. 

The  bacterial  ferments  or  en^symes  as  they  are 
popularly  called,  are  tliose  substances  which  in  the 
smallest  amounts  are  capable  of  effecting  great  chemical 
metamorphotic  changes  without  undergoing  any  change 
themselves.  According  to  Fermi,  bacteria  may  be 
destroyed  with  certain  antiseptic  solutions,  which,  however, 
in  no  way  affect  the  ferments.  Such  antiseptics  are  car- 
bolic acid,  3  per  cent. ;  thymol,  1  per  cent. ;  chloroform 
and  ether. 

The  action  of  the  ferments  may  be  observed  through  the 
liquifaction  of  their  gelatin  media.  This  peculiarity  of 
dissolving  gelatin,  an  albuminoid  substance,  is  a  property 
of  the  majority  of  bacteria;  hence  we  hQ.\e2i\\  albuminoid 
dissolving  ov  proteolytic  ferment.  For  this  euzymotic  action 
an  alkaline  is  the  most  favorable  medium.  Acids  dis- 
turb its  function  considerably.  It  was  formerly  believed 
that  the  ferment  concerned  Avas  pepsin,  a  bacterial  product, 
but  as  pepsin  acts  only  in  an  acid  medium  it  is  highly  prob- 
able that  trypsin  is  the  active  agent,  for  it  requires  an  alka- 
line reaction  to  develop  its  function  of  dissolving  albumi- 
noid bodies.  We  shall  learn  later  that,  as  the  author  had 
determined  in  his  experiments,  this  bacterial  trypsin  plays 
an  important  role  in  such  dental  defects  as  occur  in  the 
alkaline  reaction  of  the  oral  cavity. 

The  diastatic  bacterial  ferment  which  occurs  in  the 
mouth  has  yet  to  be  considered.  This  ferment  converts 
starch  into  sugar.  Nearly  one-third  of  all  the  bacteria 
investigated  by  Fermi  possessed  this  capacity.  The  sugar 
thus  formed  becomes  injurious  to  the  teeth  after  it  has 
undergone  further  conversion  into  acid  by  the  same  or 
by  other  bacteria  which  may  happen  to  be  present. 

The  Metabolic  Products  of  the  Bacteria.    Many 


106  BACTERIOLOGY, 

of  the  bacteria  have  the  faculty  of  producing  pigments, 
which  are  either  limited  to  the  culture  or  scattered  through 
the  nutritive  media.  These  pigments  may  produce  the 
most  beautiful  colors  of  the  spectrum  as  well  as  blurred 
tinted  mixtures.  The  carotin  group  produces  a  pretty 
yellow  pigment  which  is  related  to,  if  not  identical  with, 
the  coloring  substance  of  carrots.  The  bacillus  prodig- 
iosus  produces  a  light  red  pigment  called  procligiosin.  Xan- 
thin  is  the  violet  pigment  from  the  bacterium  violaceura. 
Fluorescin  and  pjyocyanin  are  beautiful  fluorescent  colors, 
the  former  is  characteristic  of  many  forms  of  bacteria, 
while  the  latter  is  found  most  frequently  in  cultures  of 
the  bacterium  pyocyaneum  from  which  it  is  extracted  with 
chloroform. 

We  are  especially  interested  in  the  broum  and  black 
pigments  for  they  play  an  important  part  in  caries  of 
the  teeth.  They  have  as  yet  received  comparatively  little 
study.  The  dark  discoloration  of  the  carious  portion  of 
a  tooth,  when  no  other  dirt  exists,  is  claimed  by  certain 
authors  to  be  due  to  the  presence  of  the  sulphid  of  iron, 
while  others  believe  it  to  be  caused  by  bacterial  pigment. 
Both  views  are  correct,  for  Mayrmann  has  proved  that 
the  dark  bacterial  pigments  form  only  in  the  presence  of 
iron,  and  that  they  are  nothing  else  than  granular  excre- 
tions of  the  sulphid  of  iron. 

A  peculiar  activity  of  the  bacteria  is  necessary  for  the 
development  of  dental  caries.  This  activity  develops  in 
an  albumin- containing  nutritive  medium  which  is  free 
from  sugar,  and  consists  in  the  alkalinization  of  the 
medium.  Depending  upon  this  phenomena  Miller  and 
Arkovy  drew  conclusions  as  to  the  etiology  of  caries. 
Arkovy  has  even  demonstrated  that  the  bacillus  pulpce 
pyogenes  is  capable,  in  alkaline  media,  of  destroying  the 
tooth  substances.  He  terms  this  process,  in  which  prob- 
ably the  organic  constituents  of  a  tooth  are  alone  affected, 
disintegration,  the  contrary  of  decalcination,  which  occurs 
after  treating  the  tooth  with  acids. 

The  majority  of  the  different  varieties  of  bacteria  have 
the  capacity  of  converting  the  sugar,  which  is  found  in 


MORPHOLOGY  AND  BIOLOGY.  107 

the  nutritive  medium,  into  acids.  This  conversion  of 
sugar  into  acid  progresses  rapidly  under  various  influences 
with  the  formation  of  gases,  on  account  of  which  the  pro- 
cess may  also  be  looked  upon  as  fermentation.  The  chief 
acid  formed  is  lactic,  although  formic,  acetic,  butyric,  and 
propionic  acid  are  also  produced.  Lactic  acid  occurs  in 
the  form  of  a  so-called  fermentation  lactic  acid,  which 
is  know  as  ethylidene  ladle  acid,  CH3 — CHOH — COOH. 
Remnants  of  food  constantly  remain  in  the  mouth  which 
contain  carbohydrates.  The  latter,  according  to  modern 
teaching,  form  acids  which  decalcify  the  tooth  substances, 
and  lead  to  caries.  The  remaining  organic  portions  of 
tooth  tissue  are  then  destroyed  through  other  bacteria. 
The  chief  exponent  of  this  theory  is  Miller,  and  as  a 
matter  of  fact  it  is  tenable  in  most  cases. 

Tlie  belief  of  some  authors  that  the  acid  comes  from 
the  tooth  itself  through  the  decomposing  action  of  the 
bacteria  is  entirely  erroneous.  Granting  that  a  certain 
amount  of  sugar  is  found  in  the  animal  tissues,  its  supply 
is  not  enough  for  conversion  into  a  sufficient  amount  of 
acid. 

Bacteria  also  cause  a  degenerative  process  in  the  mouth, 
popularly  called  putrefaction.  This  is,  generally  speaking, 
a  process  in  which  the  albuminous  bodies  are  decomposed 
into  a  foul  smelling  substance.  This  change  is  begun  by 
the  above  described  proteolytic  enzyme  wdiich  peptonizes 
the  albuminoid  bodies ;  the  resulting  substance  is  still 
further  decomposed  by  the  activity  of  various  bacteria. 

The  products  of  putrefaction  are  :  albumose,  ammonia 
and  amine,  leucin,  tyrosin  and  other  amido-bodies  ;  fatty 
acids,  indol,  skatol,  phenol,  mercaptan,  sulphuretted 
hydrogen,  carbonic  acid,  hydrogen,  and  occasionally  pit 
gas. 

Dental  caries  is  also  usually  designated  as  putrefaction, 
a  term  which  various  authors  have  protested  on  the  ground 
that  the  typical  signs  accompanying  putrefaction,  particu- 
larly the  putrefactive  odor,  fails  in  caries  of  the  dentin. 
It  must  be  admitted,  of  course,  that  i)utrefaction  docs  not 
occur  in  the  teeth  in  the  customary  sense.     The  tooth  sub- 


108  BACTERIOLOGY. 

stances  are  too  hard  for  this,  and  the  conditions  of  the 
mouth  are  not  favorable,  as  the  teeth  are  being  constantly 
bathed  in  saliva.  We  can,  however,  hardly  apply  any 
other  term  to  a  process  in  which  the  tooth  substances 
become  softened  and  destroyed,  and  in  which  this  destruc- 
tion is  brought  about  by  bacteria  which  are  able  to  destroy 
the  organic  ground  substance  of  teeth.  It  is  this  pepton- 
izing of  the  albuminoid  substance  which  is  strongly  indic- 
ative of  a  real  putrefactive  process. 

Specific  putrefactive  bacteria  are,  as  a  fact,  found  in 
large  quantities  in  carious  teeth ;  they  can  be  cultivated 
from  the  sections  of  the  softened  dentin.  If  in  the  course 
of  progress  the  caries  affect  the  pulp,  the  putrefactive  bac- 
teria will  also  be  found  to  be  the  exciting  factor  of  the 
septic  process.  They  are  the  agents  which  generate  a 
greater  or  less  amount  of  gas  by  means  of  the  decomposi- 
tion products  of  the  tooth  pulp.  When  this  putrefactive 
gas  cannot  escape  it  exerts  pressure  upon  the  root  perios- 
teum, and  thus  causes  painful  sensations.  The  presence 
of  such  imprisoned  gases  may  be  detected  by  applying 
heat  which  causes  the  gas  to  expand,  and  therefore  the 
pain  to  increase.  Likewise  the  pain  is  relieved  by  opening 
the  pulp  chamber  and  permitting  the  gas  to  escape. 

Following  are  the  most  important  of  the  gases  gener- 
ated by  bacteria  : 

Sulphuretted  hydrogen  which  is  derived  from  the  albu- 
min of  the  pulp.  Its  detection  is  simple.  Paper  which 
has  been  soaked  in  lead  acetate,  if  held  in  the  presence 
of  this  gas  when  still  moist,  is  stained  black. 

The  vapors  of  the  putrid  mercaptan,  which  are  recog- 
nized by  the  fact  that  they  change  the  reddish  isatin-sul- 
phuric  acid  into  green.  They  also  originate  from  the 
albumin." 

Carbonic  acid,  hydrogen  and  j^it  g<^is.  These  are  devel- 
oped from  the  carbohydrates  and  fat. 


THE  PATHOGENIC  ACTION  OF  BACTERIA.     109 


THE  PATHOGENIC  ACTION  OF  BACTERIA. 

Pathogenic  or  disease-producing  bacteria  are  those 
which,  through  the  formation  of  poisonous  ferments  or 
poisonous  metabolic  products,  are  able  to  injure  the  ani- 
mal organism.  Hence  the  bacteria  described  above  are 
pathogenic  to  the  oral  cavity  ;  for,  by  forming  acids,  gen- 
erating gases,  and  destroying  albuminoid  substances,  they 
act  upon  the  teeth  and  cause  them  to  present  visible  path- 
ologic phenomena. 

Several  bacteria  which  are  known  to  be  pathogenic  have 
been  found  to  generate  poisonous  substances.  These 
include  the  diphtheria  bacillus,  bacillus  of  tetanus,  chol- 
era bacillus,  the  pus-forming  bacilli,  etc.  In  other  bac- 
teria this  chemical  process  has  not  been  demonstrated,  and 
up  to  the  present  time  their  action  has  remained  unex- 
plained. This  is  true,  for  instance,  of  swine-erysipelas 
and  anthrax.  Up  to  the  present  time  no  bacteria  have 
been  discovered  in  any  part  of  the  healthy  human  organ- 
ism, excepting  in  the  lymph  glands.  Various  signs,  how- 
ever, indicate  that  micro-organisms  may  circulate  in  the 
blood  stream.  This  explains  the  occurrence  of  secondary 
pulp  inflammation  and  root  periosteal  disease,  which  may 
occur  months  and  even  years  after  treatment.  This  dem- 
onstrates the  fact  that  a  tooth  Avhich  has  once  been  dis- 
eased always  presents  a  loci  minoris  resktentce,  which  the 
bacteria,  circulating  in  the  capillaries  select  in  preference 
as  a  habitat. 

Inasmuch  as  in  an  apparently  intact  tooth  the  pulp 
may  occasionally  become  diseased  or  undergo  complete 
gangrenous  decomposition,  it  must  be  concluded  that  bac- 
teria are  at  times  found  in  the  healthy  pulp  tissue.  The 
author  decided  to  determine  this  point  by  studying  a  num- 
ber of  healthy  teeth  in  reference  to  the  presence  of  bacteria. 
A  bacteriologic  investigation  was  made  of  a  number 
of  absolutely  healthy  teeth  which  had  to  be  removed  for 
special  reasons.  The  freshly  extracted  teeth  were  washed 
in  hot  soda  solution,  then  dried,  rubbed  with  ether,  and 
passed  through  a  flame  in  order  to  destroy  the  superficial 


110  BACTERIOLOGY. 

bacteria.  Next,  the  tooth  was  split  longitudinally  with  a 
pair  of  sterilized  forceps,  and  the  pulp  immediately  placed 
in  a  medium  of  gelatin  and  agar.  In  splitting  the  tooth 
precaution  was  taken  to  exclude  the  micro-organisms  of 
the  air  by  protecting  the  tooth  with  cotton  from  which  it 
was  allowed  to  fall  directly  into  the  culture  medium.  This 
was  then  placed  in  an  incubator.  Out  of  ten  cultures, 
seven  remained  sterile  and  three  developed  bacteria.  Of 
the  three  positive  cultures,  one  culture  grew  twice,  and 
two  cultures  once.  Hence  it  is  demonstrated  hacteriolog- 
ically  that  micro-organisms  may  occasionally  be  found  in 
perfectly  healthy  teeth. 

Whether  these  apparently  healthy  individuals  from 
whom  these  teeth  were  obtained  were  in  reality  not  sub- 
ject to  some  latent  disease  through  which  the  presence  of 
the  bacteria  might  be  accounted  for  could  not  of  course 
be  determined.  For  us,  however,  this  question,  as  well 
as  that  of  the  origin  of  the  bacteria,  is  wholly  irrelevant. 
The  fact  that  in  healthy  teeth  the  pulp  may  harbor  bac- 
teria, which  probably  are  carried  thither  by  the  blood 
stream,  is  sufficient  for  the  explanation  of  the  etiology  of 
pulp  diseases,  and  associated  periostitis  which  formerly 
were  unsatisfactorily  accounted  for. 

STAINING  METHODS. 

The  dentist  should  be  thoroughly  familiar  with  the 
technic  of  staining,  because  it  is  necessary  to  detect  the 
most  important  of  the  micro-organisms  occurring  in  the 
sputum  and  in  the  oral  cavity.  Detection  of  the  tubercle 
bacilli  requires  particularly  precautionary  methods. 
Because  of  the  importance  of  the  subject  we  will  discuss 
the  methods  of  staining  this  bacillus  in  detail.  The 
principle  of  staining  the  tubercle  bacilli  depends  upon  the 
faculty  that  it  possesses  of  becoming  slowly  but  intensely 
impregnated  with  certain  staining  substances,  and  con- 
trary to  the  majority  of  other  bacteria,  retaining  the  stain 
after  it  has  once  been  absorbed  with  much  tenacity.  The 
technic  usually  employed  is  as  follows : 


STAINING  METHODS.  Ill 

A  minute  portion  of  the  sputum  is  dropped  on  a  cover 
slip  and  a  second  cover  slip  passed  over  it,  so  that  both  are 
covered  with  a  thin  film.  The  specimens  of  sputum  are 
allowed  to  dry  in  the  air  and  then  rapidly  passed  a  num- 
ber of  times  with  the  smear  side  up,  through  the  flame  of 
a  Bunsen  burner.  The  cover  slips  are  then  immersed  for 
two  minutes  in  a  heated  staining  solution.  For  this  pur- 
pose the  best  is  the  Ziehl-JSfeelsen,  which  is  composed  of 

Fuchsin,  10  gr. 

Alcoholus  absolutus,  10.0  c.c. 

5  per  cent,  carbolic  acid,  100.0  c.c. 

At  first,  as  a  result  of  this  stain,  all  the  morphotic  con- 
stituents of  the  sputum  form  a  diffuse  colored  mass,  so 
that  it  is  impossible  as  yet  to  detect  the  tubercle  bacilli. 
To  bring  them  to  view  a  30  per  cent,  solution  of  nitric 
acid  is  allowed  to  act  upon  the  preparation,  until  it  appears 
colorless  to  the  naked  eye.  After  it  is  thoroughly  washed 
in  water  and  again  dried,  the  cover  slip  is  fixed  upon  the 
slide  with  a  drop  of  Canada-balsam.  The  microscopic 
examination  of  a  specimen  of  sputum  prepared  in  this  way 
will  show  the  red  stained  tubercle  bacilli  standing  forth 
prominently  from  the  surrounding  decolorized  area. 

The  baciUi  of  influenza  which,  according  to  Pfeiffer, 
occur  in  large  numbers  in  the  sputum  of  patients  afflicted 
with  that  disease,  are  best  stained  with  carbol  fuchsin. 
They  are  observed  to  be  short  rods  about  0.4  mm.  long, 
the  rounded  ends  of  which  are  more  intensely  stained 
than  tlie  central  portions.  If  it  be  desirous  after  staining 
to  substantiate  the  diagnosis  by  cultivation  of  the  bacillus, 
it  must  not  be  forgotten  that  the  bacilli  of  influenza 
thrive  be.st  in  a  nutritive  medium  containing  hemoglobin. 

The  diplocnccns  pnnononice  of  Frankel  is  frequently 
seen  in  preparations  that  are  obtained  from  the  mouth  ; 
and,  indeed,  even  though  few  in  number,  they  may  occur 
in  a  perfectly  healthy  oral  cavity.  This  micro-organism 
is  characterized  by  two  lancet-shaped  cocci  (di])lococci) 
surrounded  by  a  capsule,  and  so  placed  that  their  blimt 
ends  lie  in  juxtaposition.    They  are  best  demonstrated  by 


112  BACTEBtOLOGY. 

first  staining  with  anilin  water  and  fuchsin,  and  then  with 
a  weak  aqueous  solution  of  methylene  blue.  Stained  in 
this  manner  the  cocci  show  a  pretty  blue  color,  and  the 
capsules  a  rose-color. 

The  diplococcus  pneumonia  is  the  exciting  cause  of  a 
whole  series  of  disease.  Those  which  interest  us  the 
most  are  the  following  :  Pneumonia,  both  croupous  and 
catarrhal ;  parotitis  (mumps) ;  osteomyelitis  ;  periostitis ; 
abscess  and  general  sepsis. 

Loffler's  bacillus  of  diphtheria^  is  not  only  found  in  the 
mouth  of  a  diphtheritic  patient,  but  also  occasionally, 
although  few  in  number,  in  a  healthy  person.  They 
form  fairly  long  curved  rods  the  ends  of  which  are  some- 
what thickened,  and  frequently  two  lie  together.  They 
are  best  stained  according  to  Gram's  method,  by  which 
procedure  other  bacteria  which  may  be  accidentally  present 
are  decolorized,  while  the  bacillus  of  diphtheria  retains  its 
stain. 

The  leptothrix  buccalis  which  occurs  in  the  mouth  in 
large  numbers  and  probably  without  any  pathologic  sig- 
nificance, is  easily  recognized  by  its  thread-like  form. 
This  micro-organism  is  of  interest  inasmuch  as  it  undoubt- 
edly takes  part  in  certain  destructive  processes  in  the  oral 
cavity.  The  majority  of  the  bacteria  of  the  leptothrix 
genus  are  colored  blue  by  Lugol's  iodin  solution. 

Other  bacteria,  such  as  the  cocci,  bacilli,  sarcince,  etc., 
also  probably  take  part  in  the  destructive  processes. 

Actinomyces  bovis  (Harz)  have  been  rarely  found  and 
to  the  present  time,  only  in  the  mouths  of  patients  suffer- 
ing with  actinoraycosis\  These  fungi  are  foimd  in  the 
pus  from  actinomycotic  abscesses  in  cattle.  They  are 
composed  of  small  greenish-yellow  granules,  1  mm.  in 
diameter,  and  consist  of  threads  and  nodular  fungi.  These 
threads  are  intertwined  like  a  skein,  from  which,  as  a 

1  Bernheim  has  found  two  organisms  constantly  present  in  stomatitis 
ulcerosa,  from  which  it  may  be  judged  that  they  bear  an  etiologic  relation- 
ship to  each  other.  The  one  resembles  the  diphtheritic  bacillus,  except 
that  it  is  larger  and  has  closed  pointed  ends,  and  does  not  stain  with 
Gram's  method.  The  other  organism  is  a  spirochseta  which  also  fails 
to  stain  according  to  Gram's  method. 


DISEASES  OF  THE  MOUTH.  113 

center,  they  radiate  in  all  directions  like  thickened  needles 
with  club-shaped  extremities.  Most  frequently  the  infec- 
tion follows  the  chewing  of  grasses  and  grains,  and  there 
is  danger  of  its  transmission  to  those  working  around  cattle. 

The  point  of  entrance  of  this  organism  into  the  body  is 
occasionally  a  cuspid  tooth,  first  penetrating  the  root 
canal  and  from  there  traveling  into  the  substance  of  the 
jaw.  As  this  micro-organism  is  easily  recognized,  it  is 
not  necessary  to  stain  it. 

Of  the  mould  fungi  which  occur  in  the  mouth,  we  are 
chiefly  interested  in  the  pathogeny  of  the  oidium  albicans 
(Rees  considers  this  as  belonging  to  the  yeast  fimgi-6ac- 
charomyces  albicans — while  Plaut  classifies  it  with  the 
torulacte — Monilia  Candida.)  This  fungus  gives  rise  to  a 
mycotic  disease  known  as  thrush.  It  forms  circumscribed 
whitish  specks  on  the  mucosa  of  the  mouth.  The  best 
method  of  examining  the  thrush  fungus  is  to  scrape  off 
a  bit  of  the  white  deposits,  but  in  so  doing  avoid  injuring 
the  mucous  membrane  as  much  as  possible.  The  scrapings 
are  placed  in  a  drop  of  a  watery  solution  of  liquor  potassse 
in  order  that  the  fungus  may  separate  from  the  epithelium. 
Without  staining  the  preparation,  it  is  then  placed  under 
the  microscope.  Morphologically,  two  constituent  parts 
are  to  be  distinguished.  Tiie  one  is  a  round  to  oval  for- 
mation reflecting  light  strongly  and  is  plainly  seen  to  be 
budding,  like  the  real  yeast  fungus.  These  buds  are  the 
spores.  The  other  part  consists  of  masses  of  threads 
which,  lying  between  the  sphericles  are  branched  and 
considerably  intertwined,  and  are  called  the  inycelia.  The 
mycelia  do  not  develop  on  our  artificial  nutritive  media; 
a  slight  acidity  seems  to  favor  their  cultivation. 

DISEASES  OF  THE  MOUTH. 

CATARRHAL  STOMATITIS. 

Catarrhal  inflammation  of  the  oral  mucous  membrane  is 
usually  the  result  of  neglect  in  tlie  care  of  the  mouth  and 
teeth.  Mechanical  influences  such  as  the  sharp  edges  of 
a  tooth,  tartar,  and  occasionally  a  poorly  fitting  plate 


114  DISEASES  OF  THE  MOUTH. 

PLATE   13. 

a.  Typhoid  ulcer  on  the  anterior  surface  of  the  anterior  palatine 
arch.  Tongue  coated,  b.  Mercurial  stomatitis.  Gums  reddened,  relaxed 
and  swollen. 

cause  a  chronic  irritation  of  the  mucosa  of  the  mouth. 
Tobacco  and  alcohol,  when  indulged  in  to  excess,  irritate 
by  their  chemical  action.  In  chlorosis  and  anemia,  as 
well  as  in  all  of  the  cachetic  diseases,  we  often  notice 
inflamed  areas.  It  is  generally  known  that  diseases  of 
the  stomach  are  frequently  accompanied  by  inflammation 
of  the  oral  mucous  membrane. 

Early  in  the  disease  the  symptoms  consist  only  of  a 
reddening  of  that  portion  of  the  gum  which  surrounds 
the  neck  of  the  tooth.  Reddening  of  other  parts  of  the 
mucous  membrane,  such  as  the  regions  about  the  arch  of 
the  palate,  occurs  very  rarely  at  the  beginning.  Gradually 
the  inflammatory  process  spreads  to  the  neighboring  areas, 
the  redness  is  accompanied  by  swelling  and  increased 
secretion,  and  the  gum  becomes  relaxed  and  lies  loosely 
upon  the  teeth.  Although  in  many  cases  a  considerable 
increase  in  the  secretion  of  a  thin  and  watery  saliva  occurs, 
yet  we  have  also  observed  cases  in  which  the  whole 
mucous  membrane  w^as  covered  with  a  tenaceous,  stringy 
mucus.  The  tongue  is  usually  coated,  while  in  severe 
cases,  the  remaining  surfaces  of  the  mouth,  are  covered 
with  a  whitish  coat.  The  patients  have  an  offensive  fetid 
breath.  The  sensitive  mucous  membrane  interferes  vfith 
speaking  and  mastication,  and  the  general  health  may  be 
impaired,  especially  if  fever  develop. 

Under  the  microscope  a  bit  of  the  coating  scraped  from 
the  mucosa  shows  various  cell  formations  which  consist 
of  desquamated  epithelium  and  extravasated  white  blood- 
corpuscles  (pus  cells).  Altered  remnants  of  food  are  also 
always  present  together  with  numerous  cocci,  bacilli, 
leptothrix,  and  mould  fungi. 

Bearing  the  etiology  and  the  patho -anatomic  findings 
in  mind,  the  treatment  consists  first  in  a  thorough  cleans- 
ing of  the  mouth.  All  deposits  should  be  carefully 
removed  from  the  teeth  and  the  mucous  membrane  ;  the 


Tab.  13. 


a 


ULCERATIVE  STOMATITIS.  115 

tartar  should  be  loosened  from  the  teeth  with  suitable 
instruments,  and  then  the  teeth  thoroughly  cleaned  with 
brush  and  powder,  or  washed  with  a  weak  acid  solution. 
If  the  latter  be  employed,  it  must  be  immediately  neu- 
tralized by  applying  powdered  chalk.  If  the  mucosa  is 
not  too  tender,  the  coating  may  be  removed  with  a  pledget 
of  cotton  soaked  in  ether.  Sharp  edges  of  teeth  must  be 
ground  smooth  and  diseased  roots  extracted. 

The  after  treatment  consists  in  ordering  an  antiseptic 
mouth  wash  like  potassium  permanganate  of  which  enough 
crystals  are  added  to  a  glass  of  water  to  produce  a  rose- 
red  color.  Other  efficient  mouth  washes  are,  a  2  per 
cent,  solution  of  potassium  chlorate,  a  3  per  cent,  solution 
of  hydrogen  peroxid,  and  a  1  per  cent,  solution  of  chino- 
sol  applied  daily  to  the  patient's  mucous  membrane  by 
means  of  a  brush. 

In  chronic  cases  iodoform  powder  should  be  rubbed 
into  the  relaxed  gums.  Painting  the  gums  with  subli- 
mate (0.05  :  50.0  water)  is  also  advocated. 

ULCERATIVE  STOMATITIS. 

Ulcerative  stomatitis,  [stomacace,  cancrum  oris)  is  often 
an  accompaniment  to  catarrhal  inflammation,  but  it  occurs 
only  rarely  as  a  local  affection.  Usually  it  is  caused  by 
various  general  diseased  conditions.  In  scorbutus  it 
occurs  regularly  and  is  accompanied  by  frequent  profuse 
hemorrhages  from  the  mucous  membrane.  This  is  called 
the  scorbutic  form  of  ulcerative  stomatitis.  In  mercurial 
cures  the  continuous  excretion  of  mercury  through  the 
salivary  glands  has  an  injurious  effect  upon  the  oral 
mucous  membrane  and  sets  up  a  severe  inflammation 
which  is  known  and  dreaded  as  the  mercurial  stomatitis. 
(Plate  13,  b).  A  severe  type  of  cancrum  oris  frequently 
follows  leukemia ;  its  form  is  similar  to  that  observed 
in  workers  in  chemical  factories  who  have  become  diseased 
from  the  poisonous  products.  Another  peculiar  type  of 
stomatitis  is  characterized  bv  circumscribed  yellowish 
specks  on  the  velum  palati   in   typhoid  fever,     Plate  13 


116  DISEASES  OF  THE  MOUTH. 

shows  a  photograph  of  such  a  case,  which  Professor  F. 
Mliller  kindly  furnished. 

This  disease,  which  is  rarely  uniform,  is  especially  char- 
acterized by  more  or  less  scattered  ulcers  covering  the 
mucous  membrane,  which  has  been  altered  by  inflam- 
mation. The  chief  location  of  the  ulcers  is  the  border  of 
the  gums  which  becomes  swollen,  relaxed  and  later  under- 
goes necrosis.  Sometimes,  although  rarely,  the  gums 
remain  comparatively  intact,  while  the  buccal  mucosa, 
especially  in  the  region  adjacent  to  the  teeth,  as  well  as 
the  rest  of  the  oral  mucous  membrane,  is  attacked  in  pref- 
erence. The  most  obstinate  and  the  last  to  respond  to 
treatment  are  those  ulcers  which  are  situated  at  the  angle 
of  the  lower  jaw. 

Cancrum  oris  occurs  quite  frequently  in  children  at  the 
time  when  they  shed  their  first  teeth.  Frequently  all  the 
children  of  a  school  suffer  simultaneously  from  this  affec- 
tion, and  the  epidemic-like  manner  in  wdiich  it  has  been 
observed  to  spread  among  soldiers,  factory  employees,  etc., 
favors  the  probability  of  its  contagiousness. 

Patients  suffering  from  ulcerative  stomatitis  feel  very 
weak  and  depressed.  The  odor  of  their  breath  is  even 
more  offensive  than  in  the  catarrhal  form.  Nourishment 
can  be  taken  only  with  considerable  pain  and  the  disease 
is  frequently  complicated  by  an  increase  in  temperature. 
In  consequence  of  the  suppurative  process  the  periosteum 
is  gradually  destroyed.  Then  follows  the  destruction  of 
a  portion  of  the  hard  and  soft  parts  of  the  alveolar  pro- 
cess, which  causes  the  teeth  to  become  loosened  and  finally 
to  fall  out. 

The  treatment  is  identical  with  that  of  catarrhal 
stomatitis,  only  in  addition  potassium  chlorate  must  be 
administered  internally.  Adults  receive  every  three 
hours  a  teaspoonful  of  a  solution  of  potassium  chlorate 
consisting  of  15  grains  to  the  ounce.  Children,  on  account 
of  the  toxic  action  of  this  preparation,  should  not  receive 
more  than  a  teaspoonful  of  a  2  per  cent,  solution  every 
two  hours.  The  ulcers  should  be  thoroughly  touched 
with  a  caustic  stick.    Patients  undergoing  mercurial  treat- 


APHTHOUS  STOMATITIS.  117 

ment  (inunctions)  should  wash  out  the  mouth  regularly 
with  potassium  chlorate  even  before  inflammatory  phe- 
nomena occur. 

DECUBITAL  ULCERS. 

Circumscribed  pressure  ulcers  and  decubital  indurations 
develop  not  infrequently  in  the  oral  mucous  membrane, 
and  are  due  to  tight  dental  plates  or  too  tight  corrective 
apparatus,  as  well  as  hard  tartar  and  the  points  of  carious 
teeth.  According  to  the  location  of  such  mechanical 
irritants,  either  tlie  alveolar  covering,  the  cheek,  or 
occasionally  the  tongue  will  be  affected. 

At  first  the  epithelium  is  lost,  and  later,  under  the 
influence  of  inflammatory  irritants,  an  infiltration  of  the 
subepithelial  tissue  develops.  In  time  a  firm  nodule  is 
formed  in  which  a  depression  occurs  at  the  point  of  great- 
est pressure,  and  which  undergoes  ulceration.  According 
to  many  authorities,  these  ulcers  have  often  been  the 
origin  of  benign  as  well  as  malignant  growths.  In  Fig. 
65  is  shown  a  photograph  of  such  a  case  observed  by  the 
author  in  which  a  decubital  ulcer  caused  by  a  sharp-edged 
tooth  developed  into  a  walnut-sized  fibroma. 

Treatment. — Such  pressure  ulcers  are  usually  pain- 
ful and  therefore  do  not  exist  without  the  patient's 
knowledge.  Sharp  edges  to  tooth  plates,  rough  teeth, 
etc.  must  be  eliminated  before  any  harm  has  been  done. 
If  a  surface  be  already  ulcerated,  it  must  be  touched  with 
the  silver  nitrate  stick  or  with  tincture  of  iodin,  and  the 
mouth  should  be  washed  with  an  antiseptic  solution. 

APHTHOUS  STOMATITIS. 

Aphthous  stomatitis  occurs  most  frequently  during  the 
first  two  years  of  life  in  children  who  have  been  reared 
under  unhygienic  conditions.  It  presents  itself  with 
rounded,  originally  small  specks  of  grayish-white  color 
which  later  become  fixed  together.  They  do  not  project 
beyond  the  surface,  but  on  the  contrary  are  surrounded 
by  a  somewhat    elevated  red  area.     They  bleed  easily 


118  DISEASES  OF  THE  MOUTH. 

and  are  very  painful  when  an  attempt  is  made  to  scrape 
them  off.  Hence  they  do  not  form  a  coating  to  the 
mucosa  but  consist  of  an  exudate  of  fibrin  into  the  mucous 
membrane  and  a  thickening  of  the  epithelium  wliich 
becomes  opaque.  The  surrounding  area  of  each  aphtha 
is  richly  infiltrated  with  round  cells.  This  disease  is  not 
likely  to  be  mistaken  for  thrush  or  syphilitic  plaques  as 
the  aphthae,  unlike  these  patches,  are  so  sensitive  that  the 
ingestion  of  food  causes  pain. 

The  favorite  seats  of  aphthae  are  the  cheeks  and  tongue, 
yet  they  are  not  confined  to  these  locations. 

Treatment  must  be  early  instituted  as  fresh  relapses  of 
aphthous  eruptions  tend  to  develop.  Painting  the  aphthae 
with  silver  nitrate  is  considered  quite  effective.  For  this 
purpose  a  solution  composed  of  silver  nitrate  0.10  and  of 
glycerin  25.0  is  employed.  It  is  important  also  that  the 
mouth  be  washed  after  each  meal  and  at  bed  time  with 
five  drops  of  weak  solution  (0.1  :  30.0)  of  potassium  per- 
manganate to  a  glass  of  water.  If  this  treatment  is  fol- 
lowed by  a  disappearance  of  the  aphthae,  no  loss  of  sub- 
stance results,  for  a  restitutio  ad  integrum  of  the  destroyed 
mucosa  sets  in. 


MYCOTIC  STOMATITIS. 

Mycotic  stomatitis,  (stomatomycosis  oidica)  which  is 
known  to  the  laity  as  thrush  occurs  chiefly  in  nursing 
infants,  although  occasionally  it  occurs  in  adults  who  have 
been  weakened  through  disease.  At  the  beginning  of  the 
disease  snow-white  minute  but  prominent  spots  develop 
in  favorable  areas  of  the  most  frequently  inflamed  portions 
of  the  mucosa.  These  spots  rapidly  spread  and  unite  to 
form  larger  areas,  the  color  of  which  in  time  becomes  dirty 
gray.  This  coating,  unlike  the  aphthae,  is  easily  removed 
unaccompanied  by  hemorrhage.  Microscopic  examination 
shows  a  thread-like  mycelium  as  well  as  a  variety  of  yeast 
fungi  which  many  authorities  consider  spores  (conidio- 
spores). 

The  constant  cause  of  thrush  has  not  yet  been  estab- 


ACTINOMYCOSIS.  119 

lished  with  certainty.  Some  investigators  believe  the 
etiologic  factor  to  be  a  sprouting  fungus  and  others  a 
mould  funsrus,  while  Plant  believes  it  should  be  classed 
with  the  torulacese.  Although  these  deposits  form  a 
superficial  coating  which  is  easily  removed,  yet  their 
trabecule  which  are  many  times  intertwined,  pass  through 
the  epithelial  layer  into  the  mucosa. 

The  prognosis  is  favorable  if  the  thrush  deposits  remain 
localized  in  the  oral  cavity,  but  if  they  occur  in  the 
pharynx  and  esophagus,  as  may  be  expected,  this  condition 
will  cause  considerable  body-weakness.  If  no  severe 
stomatitis  be  associated  with  the  thrush,  the  deposits  cause 
little  trouble. 

Treatment  consists  in  painting  the  deposits  with  a  dis- 
infectant followed  by  washing  with  alcohol.  Borax  is 
very  useful  for  this  purpose.  It  is  given  to  children  in 
the  form  of  honey  of  borax,  which  because  of  its  sweetness, 
is  distributed  unconsciously  by  the  tongue  and  thus  applied 
to  all  parts  of  the  mouth.  In  severe  cases  borax  is  also 
administered  internally  in  a  3  per  cent,  solution,  of  which 
children  are  given  a  teaspoonful,  and  adults  a  tablespoon- 
ful  every  two  hours. 

ACTINOMYCOSIS. 

This  disease,  which  is  contracted  from  the  actinomy- 
ces  bovis,  the  ray-fungus  of  cattle,  occurs  more  often  in 
animals  than  in  man,  and  less  rarely  in  cities  than  in  the 
country.  It  results  very  frequently  from  chewing  grains 
in  which  the  fungus  develops.  There  is  risk  of  infection 
even  in  working  about  stalls  and  barns.  Neglected  oral 
cavities  in  which  a  gingivitis  with  relaxed  gums  exists 
are  especially  favorable  to  infection  ;  and,  according  to  a 
communication  from  a  physician,  the  first  signs  of  the 
disease  begin  with  preference  in  the  immediate  neighbor- 
hood of  a  badly  diseased  tooth.  It  seems,  therefore,  that 
the  fungus  is  able  to  multiply  in  the  irritated  and  inflamed 
bony  tissue.  It  is  highly  probable  that  the  fungus  often 
reaches  the  interior  of  the  bone  through  the  pulp  cavity 


120  DISEASES  OF  THE  MOUTH. 

and  the  root  canal.  The  lower  jaw  is  the  seat  of  pref- 
erence, probably  for  mechanical  reasons. 

The  first  external  symptom  which  can  be  seen  and  felt 
is  a  slowly  developing  board-like  infiltration  over  which 
the  skin  of  the  face  is  discolored  bluish-red.  In  the  course 
of  time  this  part  of  the  skin  breaks  down  at  one  or  more 
points,  and  a  thin  watery  or  a  thick  pus-like  discharge 
appears.  The  chai'acteristic  constituents  of  this  pus  are 
yellowish-green,  pin-head  sized  granules  (actinomyces 
kernels)  which,  microscopically,  show  lumps  of  matted 
threads  from  the  periphery  of  which  club-shaped  elements 
grow  in  all  directions. 

The  prognosis  is  not  always  as  bad  as  one  is  accustomed 
to  believe,  since  spontaneous  recovery  even  in  advanced 
cases  has  been  reported.  Yet  we  must  not  place  too 
much  reliance  upon  such  an  outcome  for  the  disease  may 
be  transmitted  to  other  organs,  or  even  when  the  process 
remains  localized  upon  the  face  or  neck,  it  causes  dis- 
figuration through  discoloration  and  fistulous  formation. 

Treatment. — All  suspicious  teeth  must  be  immedi- 
ately removed  for  the  successful  combat  of  this  disease. 
The  fistulse  and  pus  foci  must  be  widely  opened  and 
cleaned  with  a  sharp  curet.  In  order  to  destroy  the  etio- 
logic  factor  as  completely  as  possible,  these  areas  must 
also  be  thoroughly  cauterized  with  the  thermocautery. 
After  surgical  intervention  the  infected  areas  should  be 
freely  powdered  with  iodoform,  "^hich  seems  almost  to  be 
specific  in  its  action. 

It  has  also  been  recommended  in  place  of  the  operative 
treatment  that  the  diseased  tissue  be  frequently  injected 
with  tincture  of  iodin.  However,  operative  treatment 
seems  to  be  the  most  reliable  and  according  to  Mikulicz 
and  Kiimrael,  it  should  be  followed  by  the  internal 
administration  of  potassium  iodid,  which  manifestly  accel- 
erates the  healing  process.  The  dose  of  the  potassium 
iodid,  depending  upon  the  age  of  the  patient,  varies  from 
15  to  45  grains  per  day. 


NOMA.  121 


NOMA. 


Noma,  or  canorum  oris,  is  a  rare  disease  which  usually 
attacks  children  reared  laider  unfavorable  conditions  of 
life.  Those  patients  are  the  most  vulnerable,  who  develop 
cancrum  oris  at  the  close  of  a  severe  illness. 

Its  first  indication  is  a  bluish-red  vesicle,  on  the  buccal 
nuicous  membrane  opposite  the  first  upper  molar.  This 
vesicle  rapidly  changes  to  black,  and  is  soon  followed  by 
considerable  swelling  of  the  cheek.  The  affected  area  in 
the  cheek  becomes  discolored  and  gradually  turns  dark, 
forming  a  hole  with  serrated  edges.  The  perforation  of 
the  cheek  is  caused  by  gangrenous  destruction,  in  which 
both  the  soft  and  osseous  tissues  are  changed  into  a  dark 
black  granular  mass. 

Inasmuch  as  this  disease  occasionally  occurs  endemi- 
cally  in  children's  hospitals,  it  is  believed  to  be  contagious. 
In  fact,  Petruschky  was  able  to  cultivate  diphtheritic  and 
pseudodiphtheritic  bacilli  from  the  diseased  foci  ;  while 
C.  Schmidt,  on  the  other  hand,  found  constantly  an  organ- 
ism that  strongly  resembled  the  necrosis  bacillus  of  Jen- 
sen. 

The  prognosis  is  unfavorable  (70  per  cent,  mortality 
rate),  for  the  disturbance  spreads  rapidly  and  finally 
becoming  general,  develops  into  and  causes  general  sepsis 
or  pneumonia.  If  the  process  remains  stationary,  facial 
defects  and  scars  result  in  most  of  the  cases.  Rare  indeed 
are  the  cases,  such  as  one  observed  by  the  author,  in  which 
the  patient  had  water  cancer  when  a  child.  This  healed 
so  thoroughly  that  when  she  became  an  adult  nothing 
remained  except  a  small  groove  in  the  cheek  which  did  not 
affect  her  beauty.  In  a  second  case  the  patient  was  an 
eight-year-old  girl,  in  Avhom  the  process  reached  a  stand- 
still, but  a  defect  resulted  about  the  size  of  a  hen's  egg. 

Treatment.  It  is  advisable  to  destroy  the  gangrenous 
area  with  the  thermocautery  and  to  paint  it  with  tincture 
of  iodin.  Internally,  alcohol  and  quinin  are  given  in  the 
form  of  the  wine  of  quinin,  from  one  to  three  table- 
spoonsful  three  times  a  day.     Washing  the  mouth  with  an 


122 


DISEASES  OF  THE  MOUTH. 


antiseptic  solution  must  not;  of  course,  be  neglected ;  for 
this  purpose  potassium  permanganate  is  employed ;  or  salol 
in  the  following  prescription  : 

R  Salol  3jss 

Spirit,  ad.  oz.  iij 

Sig. — A  teaspoonful  to  a  cup  of  water,  to  be  used  as  a  mouth  wash. 

On  account  of  the  seriousness  of  this  disease  an  experi- 
enced surgeon  should  be  consulted  at  once. 


PYORRHOEA  ALVEOLARIS  AND  ATROPHIA 
ALVEOLARIS  PRAECOX. 

Literature  furnishes  very  contradictory  statements 
regarding  the  etiology  of  alveolar  pyorrhea,  a  condition 
which  Arkovy,  because  of  the  patho-anatomic  findings, 
wished    to  call   specific   alveolar   caries  {caries  alveolaris 


Fig.  52.— Anterior  portion  of  a  macerated  lower  jaw,  which  shows  partial 
destruction  of  the  alveoli  through  pyorrhoea  alveolaris. 

specifica).  Riggs,  Galippeu,  and  others  consider  this  dis- 
ease to  be  caused  by  purely  local  injuries,  and  believe  that 
deposits  of  tartar,  through  pressure  upon  the  gums  and 
periosteum,  cause  chronic  suppuration  of  the  alveolar  pro- 
cess. According  to  Baume,  disease  of  the  periodontium 
and  the  gum  spreads  to  the  alveoli,  which  become  involved 


PYORRnCEA  ALVEOLARIS,  ETC.  123 

secondarily.  Michel  looks  upon  pyorrhea  as  the  expres- 
sion of  a  constitutional  disease  associated  with  sujjar  in 
the  urine.  Arkovy  remarks  that  pyorrhea  is  especially 
likely  to  occur  in  anomalies  of  the  position  of  teeth, 
because  of  the  unequal  pressure.  Romer  also  agrees  with 
this  opinion,  and  refers  to  the  fact  that  not  until  old  age, 
when  the  bones  have  become  rigid  and  no  longer  yield  to 
the  pressure,  does  pyorrhea  follow  the  effects  of  it. 

It  has  not  been  proved  that  a  specific  micro-organism 
is  the  cause  of  this  disease,  and  this  can  hardly  be  expected. 
However,  it  has  been  determined  by  Miller  that  micro- 
organisms are  associated  with  this  disease  process.^ 

The  8ymptoms  are  not  always  alike  ;  sometimes  the  gum 
is  swollen,  relaxed,  and  reddened  ;  at  other  times  the  gum 
sticks  to  the  neck  of  the  tooth  as  a  thin,  pale  layer. 
Pressure  upon  the  gum  about  the  tooth,  however,  always 
causes  some  pus  to  ooze  from  the  so-called  pocket  of  the 
gum.  Early  in  the  process  the  teeth  remain  tight  in  their 
cells ;  later,  however,  they  become  loosened  and  finally 
fall  out.  The  patients  notice  a  disturbance  first  when  the 
loosened  teeth  interfere  with  mastication  ;  occasionally 
they  feel  a  light  pricking  sensation  or  slight  pain. 

According  to  Romer,  the  following  jDatho-anatomic 
changes  may  result.  In  the  first  stage  no  other  change  is 
noticed  than  an  infiltration  of  round  cells  into  the  gum 
and  in  the  marginal  portions  of  the  periodontium.  It 
should  be  remembered  that  in  this  area  a  thick  bundle  of 
fibers  extends  from  the  surface  of  the  tooth  to  the  perio- 
dontium and  gums,  forming  a  dense,  tight  ring  around  the 
neck  of  the  tooth.  These  fibrils  are  the  first  to  be  des- 
troyed by  the  round  cells,  and  as  a  result,  the  ligament 
becomes  loosened  about  the  tooth,  the  pocket  refer- 
red to  above  is  formed,  and  further  extension  of  the 
infection  is  unobstructed.  Under  the  influence  of  the 
pyogenic  micro-organisms,  which  are  found  in  the  mouth, 

['  This  statement  is  in  a  measure  misleading,  It  is  to  be  expected  that 
micro-organisms  are  present  in  pus  from  pyorrhal  pockets,  but  Prof. 
Miller  distinctly  states  in  his  "Micro-organisms  of  the  Human  Mouth" 
that  he  has  been  unable  to  discover  any  specific  bacterium  in  connection 
with  this  disease. — Ed.] 


124  DISEASES  OF  THE  MOUTH. 

assisted  by  the  deposits  of  tartar,  the  alveolar  border  grad- 
ually disappears.  The  hard  crusts  of  tartar,  which  may  be 
felt  as  a  rougheniug  of  the  surface  of  the  root  in  the  pockets, 
(the  latter  having  now  become  increased  in  size),  do  not 
originate  from  the  saliva,  but  are,  according  to  Arkovy, 
dissolved  calcium  salts  that  have  been  reprecipitated.  In 
the  neighborhood  of  the  tooth-root  granulation-tissue  de- 
velops, which,  similar  to  a  root  granuloma,  is  richly  sup- 
plied w^ith  epithelial  cells.  The  latter  originate  chiefly  in 
the  epithelium  of  the  gum,  but  some  of  them  come  from 
the  epithelial  nests  in  the  root  membrane.  The  dissolu- 
tion of  the  bone  occurs,  as  is  beautifully  shown  in  Romer's 
preparations,  by  a  destruction  of  the  calcium  salts.  In 
this  process  bundles  of  the  fibers  of  Sharpey  remain 
intact  in  many  areas.  Finally,  these  fibers  are  also  sub- 
stituted by  granulation  tissue. 

It  is  highly  improbable  that,  after  the  removal  of  the 
tooth,  a  restitution  process  occurs  in  the  bony  tissue,  for 
the  periosteum  has  also  been  destroyed.  Therefore,  the 
scar  which  forms  is  composed  exclusively  of  connective 
tissue. 

Treatment  during  the  first  stage  has  favorable 
results ;  but  if  loosening  of  the  teeth  has  progressed  too 
far,  no  permanent  relief  can  be  offered.  The  most 
important  point  in  the  treatment  consists  in  thoroughly 
cleansing  the  gum  pocket,  removing  all  deposits  and  other 
foreign  substances  from  the  roots,  and  in  destroying  all 
granulation  tissue.  If,  after  this  treatment,  the  pockets 
are  daily  disinfected,  the  alveolar  ligament  may  again 
become  tense,  and  the  process  recede  in  many  cases.  Ber- 
ten  assists  the  tightening  of  the  ligament  by  excising  a  bit 
of  it,  in  order  that  the  ensuing  scar  may  contract  and 
inci'ease  the  tightness. 

The  superficial  concretions  are  removed  with  special 
instruments,  which,  however,  cannot  be  used  to  remove 
the  deposits  on  the  more  distant  portions  of  the  root. 
Such  concretions  may  be  dissolved  by  the  injection  of  a 
few  drops  of  some  acid.  The  author  employs  for  that 
purpose   a    30   per  cent,   solution  of  hydrochloric   acid 


PYORRHCEA  ALVEOLARIS.  125 

which,  through  its  caustic  action,  destroys  a  large  number 
of  the  bacteria,  and  also  the  neighboring  granulation 
tissue.  The  thorough  destruction  of  the  latter  is  of  the 
greatest  importance  to  insure  a  permanent  cure.  This  may 
be  obtaiued  by  chemical  or  mechanical  means.  AValk- 
hoff,  Romor,  and  others  cauterize  ^yith  chlorphenol  crys- 
tals, while  Baume  and  other  obseryers  adyise  burning  the 
tissue  to  a  considerable  depth  with  the  thermocautery. 

To  ayoid  a  recurrence  the  wound,  which  has  been  estab- 
lished by  this  time,  should  be  washed  out  daily.  For 
this  purpose  hydrogeu  peroxid  (30  per  cent.)  or  chinosol 
(5  per  cent.)  is  employed.  Both  of  these  preparations  may 
be  giyeu  to  a  patient  without  hesitation,  so  that  he  may 
personally  undertake  to  wash  carefully  the  wound  daily. 

If  constitutional  disease  be  at  fault  it  must  be  attended 
to  by  a  specialist. 

Atrophia  alveolaris  prsecox,  the  premature  disap- 
pearance of  the  alyeolar  process,  manifests  itself  in  a 
loosening  of  the  teeth.  All  signs  of  inflammation  of  the 
gum  and  immediate  neighborhood  are  absent.  The  cir- 
cular ligament  remains  normal,  does  not  become  relaxed, 
and  pressure  is  not  followed  by  the  appearance  of  pus ; 
tlie  teeth  become  elongated — that  is,  they  seem  to  be 
lengthened,  while  the  tooth  alyeolus  becomes  contracted  ; 
and  finally,  the  teeth  loosen  to  such  an  extent  that  the 
patient  wishes  to  haye  them  extracted,  or  they  fall  out 
of  their  own  accord.  It  will  be  obseryed,  therefore,  that 
this  process  is  exactly  like  that  accompanying  senile 
atrophy  of  the  alveolar  processes. 

This  disease  consists,  patho-anatomically,  in  an  osteo- 
porosis of  the  alyeolar  plates  with  subsequent  atrophy  of 
the  bones  ;  and  hence,  in  this  respect,  also,  it  is  identical 
with  the  senile  form.  The  roots  of  such  extracted  teeth 
frequently  haye  a  peculiar,  speckled,  transparent  appear- 
ance. 

Atrophia  alyeolaris  praecox,  contrary  to  alyeolar  pyor- 
rhea, defies  all  treatment.  Symptomatic  relief  may  be 
given  by  fastening  the  loose  teeth  to  the  remaining  firm 
ones  by  means  of  some  form  of  bridge  or  band  system. 


126  DISEASES  OF  THE  MOUTH. 

PAROTITIS  (MUMPS)* 

Inflammation  of  the  parotid  gland  follows  either  a 
severe  infection  (metastatic),  or  it  occurs  as  primary  idio- 
pathic jxir otitis.  Adults  as  well  as  children  are  subject  to 
this  disease,  which  occurs  either  epidemically  or  endemi- 
cally.     Old  people  and  infants  seem  to  be  immune. 

After  an  incubation  period  of  fourteen  days  one  side  of 
the  face,  and  more  rarely,  both  sides,  become  swollen,  both 
in  front  and  below  the  lobe  of  the  ear,  which  is  drawn 
upward.  Fever  develops  and  the  swelling  rapidly 
increases  so  that,  together  with  a  collateral  edema  of  the 
cheek,  the  face  becomes  considerably  deformed.  The 
patient  suffers  less  from  the  pain  than  from  difficulty  in 
speaking,  chewing,  and  swallowing. 

The  prognosis  is  favorable,  since  complete  recovery 
occurs  generally  in  from  eight  to  fourteen  days. 

As  infection  may  travel  from  the  mouth  through  the 
duct  of  Stenson,  disinfection  of  the  oral  cavity  is  indi- 
cated. Other  therapeutic  measures  consists  in  the  regu- 
lation of  the  bowels  and  in  the  rubbing  of  potassium 
iodid  ointment  into  the  affected  regions,  in  order  to  check 
the  spread  of  the  disease,  and  to  accelerate  the  resolution. 

SYPHILIS. 

The  oral  cavity  is  very  frequently  the  seat  of  the 
primary  lesion  of  syphilis,  but  secondary  and  tertiary  luetic 
processes  may  also  select  this  part  of  the  body. 

Many  cases  are  recorded  of  primary  affection  in  the 
mouth.  This  fact  is  not  at  all  extraordinary  when  it  is 
considered  how  frequently  the  lips  are  the  seat  of  erosions 
and  rhagades,  and  how  frequently  the  oral  mucous  mem- 
brane presents  more  or  less  slight  injuries. 

The  infection  is  transmitted  either  directly  from  person 
to  person  (in  infancy  from  the  breast  of  the  wet-nurse), 
through  kissing,  by  the  hands  of  the  operator,  etc.,  or 
indirectly  by  various  things  which  have  come  in  contact 
with  syphilitics,   such   as  eating  and  drinking  utensils. 


SYPHILIS.  127 

cigars,  pipes,  surgical  or  dental  instruments,  toothpicks, 
etc.  Since  attention  has  been  called  to  these  various 
means  of  infection,  the  literature  has  brought  to  light  an 
endless  number  of  cases  of  luetic  primary  infection  of  the 
oral  cavity.  From  much  experience  it  may  be  asserted, 
without  exaggeration,  that  the  majority  of  all  extra- 
genital hard  chancres  occur  in  the  mouth. 

The  appearance  of  such  a  primary  affection  is,  first  of 
all,  a  small  superficial  defect,  which  consists  of  a  round, 
hard  but  elastic,  shallow  depression  surrounded  by  a  red- 
dened eminence.  Tliis  defect  spreads  rapidly  and 
becomes  covered  with  a  hard  adherent  scab  of  a  yellowish- 
brown  color.  An  infiltration  of  more  or  less  degree  of 
the  immediate  neighborhood  occurs  nearlv  always  in  the 
course  of  the  process,  as  well  as  swelling  of  the  regional 
lymph  glands. 

The  subjective  si/mptoms  usually  do  not  vary  in  propor- 
tion to  the  severity  of  the  disease,  and  manifest  them- 
selves only  throup-h  a  certain  amount  of  stretchino;  of 
the  neighboring  tissues  ;  and,  indeed,  depend  largely  upon 
the  site  and  extension  of  the  affection.  A  disturbance  in 
speecli  and  mastication  may  result. 

If  convinced  that  the  condition  is  a  hard  chancre  and 
not  a  tubercular  or  decubital  ulcer,  a  malignant  growth 
or  a  tertiary  syphilitic  lesion,  it  is  necessary  to  inform  the 
patient  immediately,  and  refer  him  to  a  physician  for 
energetic  treatment. 

The  prognosis  is  favorable  when  treatment  is  begun 
immediately,  provided  the  affection  does  not  assume  a 
phagedenic  character. 

The  dentist  also  observes  secondary  symptoms  quite  fre- 
quently, and  therefore  it  is  necessary  to  refer  to  them, 
although  briefly.  The  characteristic  signs  of  secondary 
lues  are  the  so-called  mucous  patches  (plaques  opalines), 
which,  in  their  developmental  stage,  consist  of  milk-white 
and  pearl-gray  whitish  round  specks.  These  patches  are 
somewhat  elevated  above  the  surface  of  tlie  mucosa  and 
are  surrounded  by  a  hyperemic  limitating  zone.  They 
are  adherent  at  their  lower  surfaces,  and  therefore  attempts 


128  '    DISEASES  OF  THE  MOUTH. 

to  remove  them  cause  hemorrhage.  They  occur  most 
frequently  near  carious  teeth,  the  rough  edges  of  which 
irritate  the  tissue.  In  a  like  manner  irregularly  set 
teeth,  especially  those  which  exert  pressure  upon  the 
mucosa,  are  likely  to  set  up  an  irritation  and  thus  favor 
the  development  of  mucous  patches. 

The  symptoms  vary  considerably ;  the  majority  of  the 
patients  experience  no  pain  whatever,  or  they  complain 
only  of  an  itching  irritation  or  a  slight  burning,  and  do  not 
take  notice  of  their  disease  and  consult  a  physician  until 
they  observe  a  swelling  of  the  cervical  lymphatic  glands. 

A  peculiar  form  of  this  affection  consists  chiefly  in 
involvement  of  the  gum  in  the  form  of  ulcerating  stom- 
atitis, which  is  often  followed  by  loosening,  and  finally  by 
loss  of  the  teeth. 

It  happens  occasionally  that  the  specific  patches  spread 
toward  each  other  and  becoming  confluent,  present  a  clin- 
ical picture  that  may  be  mistaken  for  croup  or  diphtheria. 

The  differential  diagnosis  is  established  by  the  fact  that 
the  course  of  syphilis  is  slower  and  unaccompanied  by 
fever.  The  diagnosis  is  also  substantiated  by  the  fact 
that  the  patient  gives  a  history  of  specific  infection,  and 
presents,  with  rare  exceptions,  other  secondary  luetic 
symptoms,  as  well  as  lymphatic  enlargements.  These 
also  serve  to  differentiate  between  syphilis  and  decubital 
ulcers,  which  may  sirailate  each  other.  The  duty  of  the 
dentist  is  limited  to  calling  the  patient's  attention  to  his 
condition,  which  is  so  highly  contagious. 

The  tertiary  syphilitic  symptoms  develop  about  three 
years,  occasionally  even  much  later,  after  the  appearance 
of  the  pi'imary  lesion.  The  most  frequent  seat  of  these 
gummatous  changes  in  the  mouth  is  the  hard  and  soft 
palate  ;  they  occur  chiefly  in  the  form  of  ulcers,  the 
immediate  neighborhood  of  which  is  firmly  indurated  ; 
or  they  consist  only  of  a  diffuse  infiltration.  The  ulcer- 
ations show  a  great  tendency  to  eat  into  the  nearby  struc- 
tures or  into  the  deeper  tissue,  with  the  result  that  open- 
ings of  varying  size  develop  between  the  oral  and  nasal 
cavities. 


TUBERCULOSIS.  129 

The  process  usually  progresses  more  rapidly  in  the  nose 
than  in  the  mouth  ;  a  characteristic  foul  odor  issues  from 
the  nasal  orifice  (ozcena  syphilitica),  and  in  further  course 
of  the  disease,  the  nasal  septum  is  destroyed,  which,  per- 
mitting the  roof  of  the  nose  to  cave  in,  produces  the  typ- 
ical picture  of  a  'sypkilitic  saddle-nose. 

Tertiary  processes  rarely  involve  the  lips,  cheeks,  and 
gums.  The  tongue,  however,  is  more  frequently  affected, 
and  as  a  result  its  lateral  aspects  which  come  in  contact 
with  the  teeth  are  covered  with  a  whitish  layer  of  thick- 
ened epithelium.  These  areas  usually  ulcerate  and  are 
slow  to  heal. 

In  conclusion,  it  should  be  stated,  that,  so  long  as  the 
inunction  or  the  potassium  iodid  cure  does  not  heal  this 
condition,  dental  treatment  should  be  excluded,  on 
account  of  the  great  danger  of  infection  both  for  the  den- 
tist and  his  patients.  After  unavoidable  and  necessary 
interference,  which  permits  of  no  postponement,  the 
hands  should  be  disinfected  with  extraordinary  care,  as 
well  as  all  appliances  which  come  in  contact  with  the 
patient.  These  appliances  must  be  boiled  in  a  solution  of 
lysol  for  at  least  one  hour.  Such  preventive  measures 
are  not  superfluous  when  we  stop  to  consider  the  sad 
records  in  the  literature  of  accidental  infection. 


TUBERCULOSIS. 

Unlike  lues,  tuberculosis  rarely  occurs  in  the  mouth. 
This  can  only  be  explained  by  assuming  that  the  mouth 
is  relatively  immune  to  the  tubercle  bacilli,  for  abundant 
op])ortunity  is  given  for  infection  through  the  air,  through 
food  (especially  milk  and  butter),  and  in  phthisical 
])atients  through  the  sputum  which  contains  masses  of 
the  bacilli.  It  has  been  reported  that  lupus  of  the 
skiu  of  the  face  has  extended  to  the  mucous  membrane 
of  the  mouth,  but  much  rarer  are  the  cases  in  which  the 
point  of  origin  is  the  mouth.  In  such  cases,  at  first 
single  minute  nodules  develoj)  on  the  mucous  membrane, 
which  later  result  in  ulcers,  the  surfaces  of  which  excrete 


130  TUMORS  OF  THE  ORAL  CAVITY. 

a  thin  watery  pus.  Later,  through  union  of  several 
ulcers,  an  extended,  ulcerated  surface  develops  which  has 
indented  edges  and  is  covered  with  a  crust.  Removal  of 
the  crust  never  causes  hemorrhage,  for  it  lies  directly  upon 
a  small  collection  of  pus,  at  the  base  of  which  the  eminence 
of  the  subsequent  tubercle  may  be  seen. 

If  the  gum  be  involved,  the  periosteum  of  the  alveolar 
processes  may  be  destroyed.  As  a  result  the  bone  under- 
goes necrosis  and  is  softened  in  toto,  or  sequestra  are 
formed  which  gradually  suppurate  and  are  discharged. 
The  roots  become  exposed  and  a  considerable  number  of 
the  teeth  are  lost. 

Tubercular  rhagades  are  furthermore  found  on  the 
dorsum  of  the  tongue  and  on  the  lips,  especially  when  hered- 
itary, progressive,  pulmonary  phthisis  is  present.  These 
rhagades  may  lead  to  considerable  loss  of  tissue  in  the 
course  of  time  if  the  patient  survive  the  tuberculous 
process,  which  is  rarely  the  case,  for  tuberculosis  of  the 
oral  cavity  belongs  to  the  gravest  of  the  symptoms. 


TUMORS  OF  THE  ORAL  CAVITY. 

BENIGN  GROWTHS. 
CYSTS. 

We  wish  primarily  to  give  a  systematic  review  of  the 
cysts,  for  on  the  one  hand,  they  play  an  important  role 
amongst  the  growths  of  the  oral  cavity,  and  on  the  other 
hand,  their  condition  is  still  subject  to  much  and  almost 
incredible  confusion. 

The  most  satisfactory  classification  of  oral  cysts  depends 
upon  their  origin,  and  therefore  the  following  varieties 
are  distinguished. 

Retention  Cysts. — Retention  cysts  have  no  connec- 
tion with  retained  teeth  in  cavities,  but  are  a  form  of 
cyst  which  develops  from  the  retention  of  the  products 
of  normal  secretion,  as  may  occur  when  the  exit  duct  of 
a  lymphatic  gland  becomes  obstructed.  In  this  manner 
the  small  glands  of  the  mucous  membrane  become  cystic 


BENIGN  GROWTHS.  131 

as  well  as  the  larger  glands,  like  the  sublingual,  which 
may  form  large  cysts  on  account  of  obstruction  to  the 
ducts  of  Bartholin  and  Rivinus  (Ranula). 

In  rare  cases  patients  are  met  whose  tongues  present 
small  elastic  growths  at  the  tip,  which  are  simply  cystic 
dilatations  of  the  glands  of  Blandin  and  Xuhu. 

Dilatation  Cysts. — Dilatation  cysts  consist  in  a  dila- 
tion of  previously  existing  or  newly  formed  cavities,  into 
the  interior  of  which  some  irritant  causes  the  secretion  of 
an  excessive  amount  of  exudate. 

Of  the  dilatation  cysts,  those  described  by  Magitot  will 
be  considered.     They  are  as  follows  : 

Periosteal  cysts,  which  originate  from  small  growths  on 
the  periosteum,  consist  of  granulation  and  epithelial  cells. 
The  interior  of  these  growths  is  easily  destroyed. 

Follicular  tooth  cysts  which  originate  in  normal  or  super- 
numerary retained  teeth  germs. 

Dermoid  Cysts. — These  owe  their  origin  to  buds  of 
the  external  skin  which,  in  the  course  of  development, 
grew  into  the  neighboring  tissue,  and  later  became  con- 
stricted from  the  epidermal  covering.  On  account  of  this 
origin,  dermoid  cysts  not  rarely  contain  various  parts  of 
the  skin,  such  as  sebaceous  glands,  hair,  nails,  and  teeth. 

Unless  certain  inadequately  described  cases  in  litera- 
ture, of  cysts  containing  multiple  tooth  contents,  belong 
to  this  category,  the  occurrence,  of  dermoid  cysts  in  the 
mouth  is  very  rare.  Of  most  interest  to  us  are  the  peri- 
osteal and  follicular  tooth  cvsts. 

Periosteal  Tooth  Cysts  (Plate  14,  Figs.  1  a,  and 
Fig,  53). — Partsch  calls  this  form  of  growth  "  perio- 
dontia! "  or  "  root-cyst  ".  These  cysts,  one  would  infer, 
occur  more  frequently  in  the  upper  than  in  the  lower  jaw, 
and  indeed,  out  of  fourteen  cases  reported  by  Partsch, 
only  one  occurred  in  the  lower  jaw,  and  of  the  one  hundred 
and  five  cases  collected  by  Julius  Witzel,  seventy-six 
belonged  to  the  upper,  and  only  twenty-nine  to  the  lower 
jaw.  There  is  no  doubt,  however,  that  they  are  as  fre- 
quent in  the  lower  jaw  as  the  upper,  only  in  the  inferior 
maxilla,  on  account  of  the  thickness  of  the  bony  cortex, 


132  TUMORS  OF  THE  ORAL  CAVITY. 

PLATE  14. 

Fig.  1.— Periosteal  Cysts. 

«.  Cy-stic  sac  which  is  attached  to  the  root  membrane.  The  accom.- 
ipanying  tooth  is  T)adly  damaged  by  caries,  the  pulp  has  undergone 
igaiigreuous  degeneration,  and  the  periosteum  is  inflamed. 

Fig.  2. — FoUiciQar  Cyst. 
a.  Cyst  with  (6)  rudimentary  tooth  structure  which  was  the  cause  of  the 
cystic  development. 

PLATE   15. 

Microscopic  preparation  of  the  root  fungosity, 
wMch  is  illustrated  in  Fig.  53  a. 
a.    Outer  layer  of  connective  tissue,     b.    Proliferation  of  epithelium. 
c.    Leukocytic  infiltration,  d.    Small  fissures  and  abscesses  which  occur 
as  well  in  the  connective  tissue  as  in  the  epithelium. 

tliey  are  not  as  likely  to  reach  the  dimensions  of  those 
in  the  superior  maxilla,  and  are  therefore  often  overlooked. 
They  also  occur  more  frequently  in  the  neighborhood  of 
the  incisor,  cuspid  and  bicuspid  teeth  than  in  that  of  the 
molars.  They  extend  in  the  direction  of  least  resistance, 
and  enlarge,  therefore,  toward  the  face, 
where  they  may  be  easily  recognized. 
These  cysts,  depending  upon  their  situa- 
tion, may  also  grow  toward  the  antrum 
of  Highmore,  and  less  frequently  toward 
the  nasal  cavity. 

They  originate  from  small,  insignificant 
growths,  at  the  tips  of  the  roots  (granu- 
loma), which  are  called  small  abscesses 
wJ3d~foo?"wUh  by  the  laity,  and  which  are  frequently 
a  granuloma  (a),  found  ou  extracted  teeth,  the  pulp  of 
sUghtiy  away  from   which    had    been    totally    destroved    bv 

the  tip  of  the  root.  nni  '       • 

gangrene.  I  he  macroscopic  appearance 
of  such  a  cyst  is  shown  in  Fig.  53  a,  and  a  microscopic 
section  in  Plate  15. 

The  development  of  such  granulomata  on  badly  diseased 
teeth  can  be  easily  explained,  for  injuries  of  any  kind  are 
likely  to  extend  to  the  root  membrane ;  and  it  is  suiv 
prising,  therefore,  that  Malassez  and  Ivirmisson  claimed 
in  their  contribution  to  have  observed  such  root  grauulo" 


Iig.l. 


Fnf.2. 


b- 


Tah.L 


fc 


d U... 


____^ 


i.-__rf 


.3  tei;?>; 


:benign  growths.  133 

mata  in  wholly  intact  teeth.  Their  development  can 
only  be  explained  by  the  fact  that  a  hematogenetic  infection 
may  have  occurred  as  a  result  of  injury. 

In  many  of  the  granuloma/ta,  cavities  may  be  detected 
with  the  naked  eye,  which  in  the  fresh  preparations  are 
filled  with  more  or  less  cloudy,  and  sometimes  pus-like 
contents.  Several  layers  may  be  distinguished  under  the 
microscope.  The  outer  layer  consists  mainly  of  concen- 
trically arranged  dense,  connective  tissue,  which  is  poor 
in  cells.  Under  this  is  a  much  thicker  layer  of  less 
dense  reticular  connective  tissue  throughout  which  many 
round  and  spindle-shaped  cells  are  scattered.  This  tissue 
jiresents  here  and  there  minute  abscesses,  or,  only  a  diffuse 
infiltration  of  leukocytes.  Especially  characteristic  of 
granuiomata  is  the  more  or  less  striking  amount  of  epithe- 
lium which  passes  through  the  remaining  tissue  in  the 
form  of  cords,  plugs,  or  occasionally,  trellis  work.  The 
epithelial  cells  generally  lie  close  together,  but  in  some 
areas  they  are  interrupted  by  minute  lacunse,  which  are 
filled  with  granular  fragments  of  degenerated  cells.  Such 
lacuhse  may  be  considered  primitive  cysts,  for  they 
develop  later  into  large  cystic  cavities,  lined  with  epithe- 
lium. It  must  be  assumed  that  the  liquid  within  the 
lacuufe  increases  in  amount,  and  the  pressure  caused  dis- 
places the  connective-tissue  layer  toward  the  periphery 
wherever  it  forms  the  outer  capsule  of  the  cystic  sac.  The 
epithelium  also  becomes  displaced,  and  is  finally  altered  into 
the  smooth  membrane  of  the  cystic  sac  lining  the  cavity, 
which  at  this  time  is  much  enlaro^ed.  Further  p:rowth  is 
probably  influenced  by  an  increase  of  the  cystic  fluid,  the 
pressure  of  which  distends  the  cystic  sac  and  tends  con- 
stantly to  displace  more  and  more  the  surroundings.  As 
a  result  the  bone  becomes  progressively  thinner,  and  is 
finally  perforated. 

The  epithelium  concerned  is  derived  from  the  masses 
epithcJUinx,  the  significance  of  which  was  explained  by 
INIalassez  and  von  Brunn.  During  the  development  of 
the  tooth  root,  a  sheath  of  epithelium,  which  is  derived 
from    the    enamel-epithelium,  has    a  form-giving    func^ 


134  TUMORS  OF  THE  ORAL  CAVITY. 

tion.  After  the  root  has  become  ossified  a  part  of 
this  epithelial  sheath  is  absorbed,  while  another  portion 
remains  in  the  root  membrane  in  the  form  of  small  nests, 
which  are  the  above-mentioned  masses  epitheliaux. 

The  diagnosis  is  made  by  external  examination  only 
when  the  size  and  situation  make  it  visible,  and  when  the 
swelling  is  palpable. 

The  nearly  spheric  swelling  grows  without  any  pain. 
Originally  it  is  of  the  consistency  of  bone  but  through  the 
progressive  loss  in  thickness  of  the  bony  substance,  it  may 
be  indented,  giving  the  parchment-like  crepitation  of 
Dupuytren. 


Fig.  54.— Periosteal  cyst  of  the  lower  jaw.  (The  diseased  portion  of  the 
tooth  which  caused  the  condition  is  not  shown  in  this  picture.)  a.  The  cyst 
sac.    b.  Bone  which  has  become  thin  through  the  growth  of  the  cyst. 

Where  portions  of  the  bone  have  become  rarefied,  it 
is  possible  to  feel  fluctuation  of  the  cystic  contents. 
Such  a  cyst,  with  the  bony  walls  arising  in  the  lower 
jaw,  is  pictured  in  Fig.  54.  This  specimen  belongs  to 
the  Pathological  Institute  of  Basle,  and  for  the  purpose 
of  reproduction  was  placed  at  the  writer's  disposal  by 
Prof.  Kaufmann. 

If  the  cyst  grows  in  the  upper  jaw  and  penetrates  into 
the  antrum,  it  is  sometimes  mistaken  for  empyema  of 
the  superior  maxillary  sinus.  Since  the  differential  diag- 
nosis cannot  be  established  by  the  symptoms,  it  may  be 


BENIGN  GROWTHS.  135 

determined  by  injectiug  a  fluid  into  the  antrum.  If  the 
fluid  be  discharged  by  the  nose,  an  empyema  may  be 
suspected ;  but  if,  on  the  contrary,  the  fluid  does  not  issue 
from  the  nose,  the  cystic  sac  presumably  closes  the  ostium 
maxillare,  an  opening  between  the  middle  meatus  of  the 
nose  and  the  antrum  of  Highmore.  Thns  the  failure  of 
the  fluid  to  flow  from  the  sinus  may  occasionally  indicate 
the  presence  of  a  cyst. 

The  cystic  contents  are  usually  described  as  a  clear  fluid, 
which  often  becomes  turbid  through  the  presence  of 
numerons  formed  elements  suspended  in  it.  Old  cysts 
usually  contain  cholesterin  crystals  which  often  occur  in 
such  great  numbers  that  the  cystic  fluid  has  a  glutinous 
consistency  and  a  glistening  lustre.  If  the  fluid  becomes 
infected  with  bacteria,  a  large  number  of  pus  cells  develop, 
so  that  an  abscess  is  simulated.  Occasionally  putrefaction 
sets  in,  detected  by  the  foul  odor  upon  opening  the  sac. 
Partsch  contributes  an  interesting  case  in  which  the  cyst 
was  filled  with  a  gelatinous  mass  composed  of  degenerated 
epithelial  cells.  This  is  the  only  case  in  which  that 
author  observed  the  undoubted  presence  of  epithelium  in 
the  cystic  contents. 

In  regard  to  the  therap}/,  the  author  recommends  that 
of  Partsch  as  being  the  simplest  and  the  most  reliable. 
According  to  his  method,  a  large  section  of  the  cystic  wall 
is  removed  ;  a  tampon  of  iodoform  inserted  for  from  three 
to  five  days,  until  the  edges  of  the  wound  are  somewhat 
healed.  At  the  end  of  that  time  the  tampon  is  removed, 
and  if  the  cyst  remain  open,  no  other  treatment  is  required, 
excepting  tlie  washing  out  of  the  cyst  with  a  weak  anti- 
septic solution  (boric  acid  5  per  cent.),  in  order  to  keep 
it  clean. 

There  is  absolutely  no  reason  for  permitting  the  tampon 
to  remain  in  the  cyst  a  greater  length  of  time,  as  is  advised 
by  some  authorities ;  for,  as  is  well  known,  the  inner  wall 
of  the  cyst  is  covered  with  epitlielium,  and  therefore  needs 
no  protection.  Indeed,  by  doing  so,  the  internal  pressure, 
which  existed  before  the  operation,  is  re-established  in  an 
artificial  way,  and  thus  shrinking  of  the  cyst  is  prevented. 


136  TUMORS  OF  THE  ORAL  CAVITY. 

If,  on  the  contrary,  the  cyst  be  allowed  to  remain  open,  it 
becomes  progressively  smaller,  and,  according  to  the  size, 
completely  disappears  in  from  six  to  eight  weeks. 

Extirpation  of  the  cyst  sac,  however,  would  be  a  scien- 
tific failure,  for  healing  by  granulation,  especially  when 
accompanied  by  suppuration,  is  much  less  satisfactory  and 
considerably  prolonged. 

Follicular  Cysts  (Plate  14,  Fig.  2).— These  rare 
cysts  are  rarely  observed  by  the  dentist,  both  because 
specialists  on  surgery  are  preferred  to  perform  the  diffi- 
cult operation  required,  and  because  the  growths  are  often 
situated  in  distant  parts.  They  have  been  seen  to  occur 
in  the  orbits,  ascending  rami  of  the  jaw,  and  in  the  palate 
bone. 

They  originate  in  retained  or  supernumerary  tooth 
germs,  which  have  been  displaced.  A  root  never  develops 
from  these  germs.  However,  such  a  germ  gives  rise  to  a 
more  or  less  completely  developed  tooth-crown,  as  is 
illustrated  in  Plate  14,  Fig.  2  b.  Follicular  cysts  often 
lodge  in  a  varying  number  of  teeth,  or  the  rudiments  of 
teeth  which  are  either  loose  or  fused  into  a  conglomerated 
mass.  The  report  published  by  Hildebrand  shows  how 
great  a  number  of  such  rudimentary  teeth  may  occasion- 
ally occur.  In  his  case  not  less  than  150  tooth-like 
elements  were  found  present  at  one  time  in  the  jaw. 

Follicular  cysts  also  possess  an  inner  lining  membrane 
of  epithelium,  which  is  derived  from  the  enamel  organ. 
These  elements  are  flat,  less  frequently  cuboidal,  or  low 
cylindric  cells,  which  in  the  deeper  layers  occasionally 
form  a  rete  malpighn  like  structure. 

This  form  of  cyst  is  accompanied  by  the  same  symptoms 
as  the  periosteal  cyst.  It  is  distinguished,  however,  from 
the  latter  by  the  fact  that  it  is  lower  in  growth,  and  not 
dependent  upon  caries  of  the  tooth. 

von  Bramann  advises  the  following  treatment :  A  hori- 
zontal incision  is  made  down  to  the  bony  covering  of  the 
cyst,  and  a  large  flap  of  mucous  membrane  and  peri- 
osteum is  dissected  loose.  Underneath  this  a  portion  of 
the   bony  wall  is  chiselled  away  so  that  the  cyst  may  be 


BENIGN  GROWTHS.  137 

palpated.  The  inner  cystic  wall  is  then  dissected 
ont  thoroughly,  and  the  flap  of  mucous  membrane  and 
periosteum  is  returned  in  place.  A  gauze  compress  is  then 
applied  in  such  a  way  that  the  periosteum  lies  lightly  and 
without  pressure  everywhere  on  the  concavity  of  the  cyst. 
This  is  very  important,  for  when  this  method  is  employed 
the  mucous  membrane  and  periosteal  flap  soon  become 
adherent  to  the  ^vail  of  the  cavity.  In  eight  days  this 
dressing  may  be  removed. 

The  most  important  feature  of  the  treatment  consists  in 
the  thorough  removal  of  the  cystic  sac,  for  otherwise  there 
may  be  a  recurrence.  In  the  case  reported  by  Kauf- 
mann,  even  after  the  complete  removal  of  a  cyst  of  the 
inferior  maxilla,  a  cylindric-celled  cancer  developed  after 
a  number  of  years.  This  emphasizes  the  necessity  of 
taking  the  above  precautionary  measure. 


Fig.  55.— Fibroma,  due  to  the  irritation  of  a  carious  tooth. 
FIBROMA. 

Of  the  fibromata  we  must  distinguish  betwen  the  suj)er- 
fieial  and  the  deep  seated.  The  superficial,  which  are 
mainly  small  growths,  develop  in  the  gums  in  the  neighbor- 
hood of  carious  teeth  (Fig.  55  and  Fig.  56,  a,  upper  illus- 
tration) ;  or  they  arise  from  the  base  of  an  alveolus.  They 
are  often  pedunculated,  but  may  possess  a  broad  base. 
An  epulis  of  the  gum  is  likely  to  be  of  soft  consistencv, 
for  the  connective-tissue  fibers  are  strewn  with  cellular 
elements.  The  latter  are  occasionally  so  numerous  that 
we  are  in  a  dilemma  as  to  whether  the  growth  is  a  fibroma 
or  a  granuloma. 


138 


TUMORS  OF  THE  ORAL  CAVITY. 


Fibromata  cause  no  direct  symptoms,  excepting  their 
interference  with  the  cleansing  of  the  teeth.     Depending 


Fig.  56. —  Upper  illustration:  a,  epulis;  b,  abscess  of  palate  in  upper  jaw. 
Lower  illustrafion :  c,  osteophytic  thickening  of  lower  jaw ;  d,  genuine 
exostosis  with  a  neighboring  smaller  one. 


upon  their  location  and  size,  they  may  also  get  between  the 
teeth  in  mastication.  In  rare  cases  they  interfere  with 
speech. 


BENIGN  GROWTHS.  139 

The  fibromata  arising  from  the  periosteum  of  the  alveo- 
lar process,  or  from  the  interalveolar  septa,  are  harder 
than  those  of  the  gums,  for  they  contain  genuine  bony 
tissue  in  the  form  of  spicules,  as  well  as  calcareous  depos- 
its. They,  too,  are  occasionally  pedunculated,  or  at  other 
times  have  a  broad  base. 

The  most  frequent  seat  of  a  fibroma  is  the  tongue,  but 
it  may  also  occur  on  the  hard  and  soft  palate,  the  inner 
side  of  the  lips  and  cheeks,  and,  as  has  been  mentioned, 
on  the  gums. 

Fibromata  are  easily  distinguished  from  malignant 
growths  because  they  are  slower  in  growth,  unaccompanied 
by  pain,  and  cause  no  infiltration  of  the  surrounding 
tissues. 

The  treatment  of  soft  jihromaia  consists  only  in  their 
removal  with  a  pair  of  surgical  scissors.  Recurrence  is 
unknown.  The  therapy  of  the  hard  groicths  is  much  more 
difficult.  As  the  degree  of  union  with  the  bone  can  not  be 
determined,  it  is  necessary  to  resect  a  considerable  amount 
of  the  tissue.  Attention  is  called  here  to  the  deep  seated 
fibromata,  which  occur  mainly  within  the  jaw  bone  and 
are  described  as  endosteal  fibromata.  They  select  in  pref- 
erence the  inferior  maxilla,  and  when  occurring  in  the 
superior  maxilla,  they  not  occasionally  grow  into  the 
antrum  of  Hip-hmore. 


CHONDROMA  AND  OSTEOMA. 

The  cartilaginous  groidhs  are  recognized  by  their 
nodular  surface  and  their  hard  consistency.  The  latter, 
determined  by  puncture,  distinguishes  them  from  bony 
growths.  The  type  of  this  tumor  is  often  obscure,  for  it 
frequently  develops  as  a  mixed  tumor  (  chondrofibroma, 
chondromyoma,  chondrosarcoma,  osteochondroma).  Chon- 
dromata  occur  very  rarely  in  the  jaw  bones,  Avhile  osteo- 
mata  are  somewhat  less  rare.  When  the  latter  are  com- 
posed of  an  excessive  amount  of  tissue  analogous  to  the 
bony  cortex,  they  are  naturally  very  hard  ( osteoma 
durum  )  ;  but  if  the  spongiosa  is  in  excess  (  osteoma  spon- 


140 


TUMORS  OF  THE  ORAL   CAVITY. 


giosum ),  they  may  be  more  easily  pierced  by  a  needle^ 
Such  a  typical  osteoma,  located  in  the  right  upper  jaw, 
is  illustrated  in  Fig.  57.  The  term  osteoma  also  includes 
little,  hard  growths  that  develop  on  the  alveolar  processes 
as  a  result  of  chronic  inflammation.     They  present  them- 


FiG.  57.— Osteoma  of  right  superior  maxilla. 


selves  either  in  the  form  of  deposits  (  osteophyte^XtwrnoT- 
like  excrescences  (  exostoses),  or  as  a  diffuse  thiefeening  of 
the  cortex  (  hyperostoses  ).  The  lower  illustration  of  Fig. 
56  shows  the  lower  jaw  of  an  old  individual,  on  which 
exostoses  have  developed. 


MALIGNANT  GROWTHS.  141 

The  prognosis  for  both  chondroraata  and  osteomata 
is  fiivorable,  yet  cases  occur  in  which  operation  is  followed 
by  recurrence. 

LIPOALA. 

The  extirpation  of  large  as  well  as  deep-lying  growths 
must  be  performed  by  surgeons.  The  fatty  tumors  are 
usually  rounded  in  form,  soft  in  consistency,  easily  palp- 
able, and  covered  with  normal  mucous  membrane.  Accord- 
ing to  Krausnick,  they  occur  most  frequently  on  the 
tongue,  and  may  assume  such  a  shape  and  size  as  to  inter- 
fere considerably  with  the  movements  of  that  organ. 
When  they  occur  in  the  floor  of  the  mouth  or  on  the 
tongue,  speech  and  mastication  are  soon  disturbed  ;  and 
they  therefore  require  early  treatment. 

The  operative  procedure  is  easily  performed,  at  least 
that  on  the  tongue  and  cheek  lipomata,  and  consists  in 
incising  the  mucous  membrane  and  plucking  the  growth 
out  by  hand.  The  manipulation,  however,  is  somewhat 
more  difficult  when  the  lipoma  grows  in  the  floor  of  the 
mouth.  In  this  case  they  must  be  resected  in  such  a 
manner  that  the  lobular  processes,  which  extend  between 
the  hyoglossus  and  the  geniohyoglossus  muscles,  are  com- 
pletely removed. 

MALIGNANT  GROWTHS. 

SARCOMA. 

These  tumors,  are  mainly  comprised  of  elements  which 
resemble  the  germ  tissue  of  the  embryo.  They  are  divided 
into:  Round-celled  sarcomata  and  Spindle-celled  sarcomata. 
The  round-celled  sarcoma  contains  small  cellular  elements 
derived  from  the  connective  tissue.  The  Iarr/e~ceUed  or 
giant-ccJJed  .sarcoma  originates  in  the  periosteum  and  is 
usually  located  on  the  structure.  The  sj)ind/e-celled  sar^ 
coma,  like  the  round-celled  sarcoma,  is  composed  of  two 
forms,  in  one  of  which  small  cells  preyail,  while  in  the 
other  large  cells  predominate. 

Tlu'y  frequently  occur,  not  as  pure   growths,  but  as 


142  TUMORS  OF  THE  ORAL  CAVITY. 

mixed  tumors,  the  interior  of  which  often  undergoes 
retrogressive  metamorphosis,  indicated  by  the  presence 
of  a  pulpy  mass.  The  latter  is  chiefly  composed  of  cells 
that  have  undergone  fatty  degeneration. 

The  tongue  is  most  frequently  the  seat  of  these  tumors, 
which  may  be  pedunculated,  have  a  flat  base,  or  even 
penetrate  deeply  into  the  substance  of  the  tongue.  They 
are  also  found  on  the  palate,  the  gums,  and  in  very 
rare  cases  on  the  lips  and  the  cheeks.  A  sarcoma  usually 
grows  very  slowly  at  the  beginning,  but  after  a  certain 
age  is  once  attained,  they  grow  much  more  rapidly.  They 
are  not  easily  palpable  as  they  are  diff'usely  intergrown 
with  the  surrounding  tissue.  The  chief  point  in  the 
diagnosis  is  the  causation  of  pain,  which  is  sometimes 
quite  considerable. 

In  the  differential  diagnosis,  syphilitic  gummatous 
nodules  may  have  to  be  considered ;  they,  however,  con- 
trary to  sarcomata,  are  usually  multiple  in  number. 

Concerning  the  treatment,  we  must  bear  in  mind  that 
sarcoma  is  ever  more  prone  to  metastatic  extension  than 
carcinoma,  and  that,  therefore,  it  must  be  removed  as 
soon  as  possible.  The  difiiise  spreading  and  growth  into 
neighboring  tissue,  requires  the  removal  of  a  considerable 
portion  of  the  surrounding  structure  with  the  growth. 
It  may,  for  example,  become  necessary  to  amputate  the 
tongue,  or  resect  a  large  portion  of  the  lower  or  upper 
jaws,  etc. 

CARCINOMA. 

Carcinoraata,  or  cancerous  grouihs,  are  highly  malignant 
because  of  their  tendency  to  grow  uninterruptedly  into  the 
surrounding  tissue.  The  lymphatics  become  involved ; 
at  first  the  nearby  lymphatic  glands,  and  later  the  more 
centrally  situated  ones.  Aside  from  this  matastatic  exten- 
sion carcinoma  also  tends  to  spread  to  the  healthy  mucous 
membrane  near  which  it  is  located  ;  for  example,  it  may 
spread  from  the  tongue  to  the  palate.  The  patients  suffer 
considerably  from  interference  with  mastication,  from 
swallowing  products  of  ulceration,  and  even  at  the  begin- 


MALIGNANT  GROWTHS.  143 

ning  from  pain.  The  high  state  of  cacliexia  is  caused  by 
the  poison  excreted  by  these  tumors.  According  to  Fr. 
Miiller,  the  specific  action  of  the  cancer  poison  causes  in 
the  organism  a  gradual  destruction  of  tiie  protoplasm. 

Cancerous  growths  frequently  develop  in  the  oml  cavity, 
and  because  of  their  great  clinical  importance  we  will 
consider  this  subject  in  greater  detail.  The  frequent 
occurrence  of  cancer  in  the  oral  cavity  may  be  under- 
stood when  we  realize  that  this  tumor,  which  begins  with 
epithelial  proliferation,  finds  a  favorable  base  for  its 
development  in  the  presence  of  mucous  membrane  and 
mucous  membrane  glands.  In  certain  cases  the  growth 
may  assume  the  character  of  glands  (adenocarciitoma). 
Their  development  consists  in  sending  gland-like  roots 
into  the  deeper  tissues  from  the  mucous  membrane.  The 
inner  surface  of  the  trabecule  is  covered  with  an  epithe- 
lial layer,  which  becoming  constantly  thicker,  finally  fills 
this  trabeculnm  with  solid  epithelial  plugs. 

The  typical  forms  of  cancer  grow  more  frequently  in  the 
oral  cavity  than  do  the  adenocarcinomata.  Between  dense 
cords  lie  nests  of  epithelium  which,  although  they  show  no 
retrogressive  metamorphosis,  present  many  cells  in  the 
process  of  mitotic  division.  The  elements  of  the  cancer 
nests,  or  so-called  cancer  cells,  undoubtedly  represent  a 
type  of  epithelial  cells,  which  are  of  a  comparatively 
large  size  and  have  large  nuclei.  Their  outer  contour, 
sometitnes  flat,  sometimes  cylindric,  may  assume  all  possi- 
ble forms,  which  result  from  the  reciprocal  pressure  exerted 
by  each  other. 

The  squamous  celled  epitheliomata,  called  cancroid, 
select  the  mucous  membrane  in  preference  because  it  is 
covered  with  squamous  epithelium.  These  tumors  grow 
either  above  the  surface  or  deeply  into  the  parenchyma 
of  the  tissue.  Their  surfaces  become  easily  inflamed, 
and  hence  often  contain  cancerous  ulcerations.  Micro- 
scopically, the  squamous  celled  epitheliomata  consist  of 
alveoli,  the  trabecuLie  of  which  are  of  the  nature  of  con- 
nective tissue  and  possess  concentrically  arranged  layers 
of  epithelial  cells. 


144  TUMORS  OF  THE  ORAL  CAVITY. 

Other  forms  of  cancer  also  grow  in  tlie  oral  cavity, 
such  as  the  hard  scirrhous  variety,  Avhich  is  comprised 
chiefly  of  a  dense  connective-tissue  stroma,  throughout 
which  only  a  few  epithelial  nests  are  scattered.  The 
medullary  carcinoma  is  also  met  with,  but  it,  on  the 
contrary,  is  much  softer  in  consistency.  It  lacks  dense 
connective-tissue  stroma  and  the  nests  are  large  and  sur- 
rounded by  only  a  small  amount  of  connective-tissue 
fibers.  Both  the  connective  tissue  and  the  cell  nests  are 
often  the  seat  of  leukocytes. 

Cancer  of  the  oral  cavity  grows  on  the  lips,  the  tongue, 
the  floor  of  the  mouth,  the  cheeks,  the  palate  and  the  gums. 

^Nlen  are  more  frequently  subject  to  cancer  of  the  oral 
cavity  than  women.  Out  of  one  hundred  cases  about 
thirty  occur  in  women.  It  is  possible  that  smoking  and 
drinking  counts  for  its  frequency  in  men  by  causing  a 
chronic  inflammation  of  the  mucous  membrane. 

Partsch  believes  that  the  relatively  frequent  occurrence 
of  cancer  of  the  lips  in  people  who  are  exposed  to  inclement 
weather  indicates  that  prolonged  irritation  of  any  kind 
favors  the  development  of  this  disease.  Cancer  of  the  lips 
is  more  frequently  located  on  the  lower  than  on  the  upper 
lip.  It  is  difficult  to  recognize  in  the  beginning,  as  it 
shows  nothing  except  a  circumscribed  thickening  of  the 
epithelial  surface  with  few  characteristics.  In  the  course 
of  the  affection  this  thickening  becomes  covered  with  crusts 
which  result  from  the  drying  of  the  sticky  secretion.  When 
the  crust  is  removed  a  red  ulcerated  surface  is  seen,  which 
according  to  the  arrangement  of  the  proliferated  epith- 
elium, presents  yellow  specks  or  larger  yellowish  areas. 

The  ulceration  soon  rises  above  the  plane  of  the  lip 
from  which  it  is  separated  by  wall-like  borders,  and  at  the 
same  time  the  surrounding  tissue  becomes  constantly 
harder  and  stifFer  through  additional  infiltration.  Finally, 
after  a  number  of  years,  movements  of  the  lip  become 
difficult ;  usually,  however,  the  process  progresses  more 
rapidly  and  is  accompanied  by  enlargement  of  the  regional 
lymph  glands. 

The  prognosis  of  cancer  of  the  lips  is  relatively  favor- 


MALIGNANT  GROWTHS.  145 

able,  since  metastasis  to  the  inner  organs  is  not  frequent. 
Partsch  obtained  a  cure  in  35  per  cent,  of  all  cases 
through  operation. 

The  treatment  consists  in  a  thorough  extirpation  of  the 
involved  focus  as  early  as  possible,  and  in  curetment  of 
the  neighboring  lymph  glands.  Inoperable  cases  with 
excessive  metastatic  extension  can  only  be  treated  syste- 
matically by  the  employment  of  analgesics. 

Cancer  of  the  tongue  is  much  more  malignant  than  that 
of  the  lips,  because  it  spreads  more  rapidly  and  is  more 
likely  to  cause  metastasis  of  the  inner  organs.  Carcino- 
matous epithelial  proliferation  develops  most  frequently 
after  loss  of  tissue  from  the  tongue ;  for  example,  on  the 
site  of  decubital  ulcer  or  on  an  old  focus  of  leukoplacia. 
Also  lingual  epithelium,  like  that  which  is  found  in  the 
glands  of  the  tongue,  may  furnish  material  for  the  disease. 

Cancer  of  the  tongue  begins  with  a  painful  ulceration, 
the  border  of  Mhich  rises  like  a  wall  and  is  surrounded 
by  hardened  tissue,  as  in  a  case  of  cancer  of  the  lip. 

Cancer  of  the  floor  of  the  mouth  is  frequently  secondary 
to  carcinoma  of  the  tongue.  In  this  case  the  tongue  soon 
becomes  adherent  to  the  floor  of  the  mouth,  which  leads 
to  disturbances  in  speech  and  mastication. 

The  'prognosis  of  cancer  of  the  floor  of  the  mouth  and 
of  the  tongue,  even  when  operated  upon  early,  is  less 
favorable  than  cancer  of  the  lips  on  account  of  the  rapid 
extension  to  distant  lymph  glands. 

Cancer  also  arises  in  the  mucous  membrane  of  the 
cheeks,  especially  in  the  areas  chronically  irritated  by 
sharp-edged  teeth.  At  the  beginning,  the  diagnosis  is 
often  mistaken  for  tuberculosis  or  decubital  ulceration, 
which  may  have  caused  this  condition.  Its  malignancy 
is  somewhat  less  than  that  of  the  tongue  and  mouth  car- 
cinoma ;  liowcver,  cancer  of  the  mucous  membrane  of  the 
cheeks  is  frequently  followed  by  disagreeable  sequelse, 
which  are  due  to  extirpation  of  the  infected  area. 

Carcinoma  of  the  hard  as  well  as  of  the  soft  palate  is 
very  rarely  a  primary  affection  ;  it  is  more  frequently 
due  to  the  extension  of  this  disease  from  neighboring 
10 


146  TUMORS  OF  THE  ORAL  CAVITY. 

structures.  Cancer  of  the  palate,  because  of  its  location, 
tends  to  spread  to  the  air  containing  cavities  of  the  face, 
including  both  the  orbital  and  nasal  cavities.  These 
growths  are  but  slightly  malignant,  so  that  a  permanent 
cure  may  follo\A^  an  early  extirpation  accompanied  by 
resection. 

Cancer  of  the  gums  is  somewhat  more  frequent  than 
that  of  the  palate.  It  is  a  squamous  celled  epithelioma 
which  grows  rapidly  into  the  deep  portions  of  the  bone. 
Its  origin  is  frequently  due  to  the  irritation  of  carious 
teeth;  Mikulicz  has  seen  it  develop  in  the  region  of  an 
extracted  tooth.  This  originally  hard  edged  and  small- 
sized  ulceration  constantly  increases  in  dimension,  until 
finally  it  involves  the  whole  jaw  bone,  the  consistency 
and  form  of  which  can  then  no  longer  be  recognized. 
The  raucous  membrane  coating  of  the  antrum  of  High- 
more  may  also  serve  as  the  origin  of  carcinoma. 

It  must  be  assumed  that  all  carcinomata  arising  in  the 
interior  of  the  jaw  bone  are  related  to  the  epithelial  nests 
of  the  periodontium  and  to  aberrant  buds  of  the  tooth 
germ.  These  centrally  situated  cancerous  growths 
spread  with  severe  neuralgic-like  pain  and  considerable 
swelling  of  the  bone. 

A  dentist  has  frequently  an  opportunity  to  restore  by- 
operation  a  portion  of  the  face  that  has  been  destroyed 
by  disease.  Some  useful  advice  on  this  subject  is  given 
by  Claude  Martin  in  his  book,  "  De  la  Prothese  Bucco- 
Faciale. " 

GROWTHS  OF  THE  HARD  DENTAL  SUBSTANCES. 

Growths  developing  in  the  pulp  and  periosteum  (polvps, 
concretions,  granulomata,  cysts,  etc.)  are  discussed  under 
the  title  of  Pulp  and  Periosteal  Diseases,  and  hence  we  shall 
only  sjieak  here  of  such  new  growths  as  arise  from  the 
specific  hard  substances  of  the  teeth. 

The  cementum  may  become  thickened  in  all  directions 
in  old  age  and  in  certain  pathologic  conditions,  thus  giv- 
ing   the    roots    a    thickened    appearance    [hypertrophy). 


GROWTHS  OF  THE  HARD  DENTAL  SUBSTANCES.   147 

Histologic  sections  show  this  thickening  to  consist  of  a 
deposit  of  lamellae  of  cement  which  are  richly  supplied 
with  cement  bodies  and  Haversian  canals. 

Such  difPuse  tumors  of  the  cementum  may  be  desig- 
nated-/i^ji^erfrop/i?/  of  the  cementum,  while  the  circumscribed 
forms  of  tumors  are  called  exostoses.  They  are  usually 
small  and  insignificant  and  only  rarely  show  their  pres- 
ence by  the  causation  of  pain  (Plate  21,  Fig.  1). 


Fig.  58.— A  bicuspid  tooth, 
the  crown  of  which  lias  been 
ground  away  down  to  the 
neck  of  the  tooth  in  order 
to  show  a  small  dentinal 
growth  arising  in  the  pulp 
cavity  (internal  odontoma). 


Fig.  59. — A  small  ex- 
ternal odontoma 
of  the  root. 


Fig.  60.— I  o)  a  regular 
second  molar  tooth 
intergrown  (6)  with 
supernumerary  teeth. 


Tumors  which  originate  in  the  structure  of  the  dentin 
are  distinguished  according  to  their  location,  as  internal 
{odontoma)  when  they  lie  on  the  wall  of  the  pulp  cavity, 
and  as  external  when  they  occur  on  the  outer  surface  of  the 
dentin. 

Internal  odontoniata  arise  from  the  odontoblasts  and 
grow  toward  the  pulp  cavity  as  is  seen  in  Fig.  58.  They 
cau.se  neuralgic  ])ains  by  exerting  pressure  upon  the  nerves 
of  tiie  pulp,  but,  under  favorable  circumstances  they  may 
remain  symptomless  and  undiscovered  for  years. 

External  odontomata  (Fig.  59)  may  also  originate  in  the 
over  production  of  dentin  which  occurs  during  the  })ro- 
cess  of  tooth  formation.  More  frequently,  however, 
separated  rudimentary  tooth  germs  are  concerned  which 
are  intergrown  with  any  regular  tooth.  This  accounts 
for  the  fact  that  odoutomata  are  frequently  composed,  not 
only  of  dentin,  l)ut  also  other  forms  of  tissue-like  cementum 
{odeo-odontoma  or  enamel  odontoma  adamantinum).  Indeed, 
whole  supernumerary  teeth  may  be  intergrown  with  regu- 


148  FRACTURES  OF  THE  LOWER  AND    UPPER  JAWS. 

lar  teeth,  as  illustrated  in  Fig.  60.  The  wholly  dentified 
odontoma  remains  stationary  but  before  it  has  reached  that 
stage  (myxoma,  fibroma  etc.)  it  tends  to  undergo  exten- 
sion, and  its  size  may  reach  that  of  a  hen's  egg. 

New  growths  of  the  enamel  (ctdamantoma)  originate  in 
the  ameloblasts  of  teeth  wdiich  are  slow  in  development. 
They  arise  from  deposits  of  separated  tooth  germs,  and 
are  therefore  congenital.  They  occur  in  preference  on 
the  border  betw^een  the  enamel  and  the  cementnra  (Fig. 
61);  more  rarely,  in  favorable  areas  of  the  roots  (Fig.  62). 


Fig.  61.— An  enamel  growth  {ada-  Fig.  62.— An  enamel  growth  near 

mantoma)  at  the  neck  of  the  second  the  apex  of  the  first  upper  molar 

upper  molar  tooth.  tooth. 

These  tumors  are  pale,  shiny,  pear-like  growths,  about 
the  size  of  a  pin  head,  which  rarely  cause  symptoms,  and 
therefore  are  only  accidentally  found  on  extracted  teeth. 
Neuralgic  pains  have  been  frequently  attributed  to  these 
growths,  and  it  must  be  admitted  that  under  certain  cir- 
cumstances such  pains  may  arise  ;  but  such  cases  are  rare. 


FRACTURES  OF  THE  LOWER  AND  UPPER 

JAWS, 

In  comparison  with  other  bones,  fractures  of  the  lower 
jaw  are  very  rare  ;  yet  of  the  bones  of  the  face  this  bone 
is  the  most  frequently  fractured.  Either  the  body  of  the 
bone  or  the  ascending  rami  may  be  affected.  Fracture  of 
the  body  of  the  jaw,  according  to  its  location,  involves 
either  the  curved  portion  of  that  bone  or  the  alveolar  pro- 


FRACTURES  OF  THE  LOWER  AXD   UPPER  JAWS.  149 

cess.     The  ascending  ramus  may  be  fractured  either  at  its 
base  or  at  the  coronoid  or  condyloid  process. 

The  most  frequent  fractures  of  the  inferior  maxilla  are 
those  of  its  body.  They  occur  with  preference  near  the 
symphysis,  therefore,  at  the  vertex  of  the  curved  portion  of 
the  body  of  this  bone.  iS'ot  infrequently,  however,  and 
especially  accompanying  extraction  of  teeth,  small  portions 
of  the  alveolar  processes  are  broken  off.  This  injury 
occurred  formerly  much  more  frequently  and  much  more 
extensively  when  the  tooth  key  was  employed. 

Fractures  of  the  lower  jaw  are  usually  simple,  and  only 
occasionally  do  they  occur  as  comminuted  fractures,  which 
are  chiefly  met  with  in  war. 

Fractures  of  the  lower  jaw  are  recognized  by  pain  in  a 
certain  area  when  an  attempt  is  made  to  chew  or  to  speak. 
Occasionally,  but  not  always,  displacement  occurs  in  the 
tooth  row.  Crepitation  is  only  rarely  absent.  Examina- 
tion is  often  made  difficult  by  swelling  of  the  soft  parts, 
especially  in  complicated  fractures  in  which  ankylosis  of 
the  joint  has  set  in. 

The  greatest  amount  of  displacement  follows  a  fracture 
in  the  neighborhood  of  the  wisdom  teeth  ;  the  musculature 
draws  the  posterior  fragment  upward,  while  the  anterior 
fragment  falls  downward  as  far  as  the  soft  tissues  permit. 
We  have  thus  far  only  considered  the  vertical  fractures  ; 
there  occur,  also,  especially  when  struck  by  an  animal's 
hoof,  in  railroad  accidents,  or  when  shot  at  close  range,  a 
combination  of  vertical  with  horizontal  lines  of  fracture. 
Commimifed  and  transverse  fracfiire.%  both  equally  rare, 
have  also  been  observed  to  follow  occasionally  these  acci- 
dents. 

If  the  deformity  of  the  tooth  row  be  great,  the  blood- 
vessels and  nerves  in  the  mandibular  canals  are  injured. 
As  a  result  of  the  stretching  and  tearing  of  the  mandibular 
nerves,  sensation  is  completely  lost  in  those  teeth  which 
lie  peri|>herally  to  the  point  of  fracture,  as  well  as  in  the 
chin  and  lip. 

Fracture  of  the  alveolar  process  is  recognized  by  the 
mobility  of  the  fragments.     The  fracture  may  involve  the 


l50  FRACTURES  OF  THE  LOWER  AND   UPPER   JAWS. 

FIGURE  63. 

Tlie  wire  splint  of  Sauer  for  fractiires  of  the  jaw  bone. 

Upper  illustration.    Showing  its  two  parts.     Lower  illustration.  lu  situ. 

outer  or  inner  wall  of  one  or  more  tooth  alveoli.  If  both 
the  buccal  as  well  as  the  lingual  wall  be  fractured,  the 
teeth  are  loosened,  provided  they  are  still  in  their  alveoli. 
It  would,  indeed,  be  a  great  mistake  if  in  fracture  of  the 
alveolar  process  the  loosened  teeth  or  loosened  fragments 
of  bone  were  to  be  removed,  for  through  the  enormous 
vitality  that  the  jaw  bone  possesses  for  regeneration,  these 
parts  usually  grow  firm  again,  and  only  rarely  die. 

In  case  of  fracture  of  the  ascending  ramus  of  the  jaw, 
the  inferior  maxilla  is  displaced  backward  on  the  aifected 
side.  This  is  also  true  when  the  condyloid  process  is 
fractured ;  in  the  latter  case,  the  patient  feels  crepitation  in 
the  joint  when  he  attempts  to  chew.  Palpation  is  not  of 
much  assistance,  for  the  soft  parts  are  usually  much  swollen. 
Fracture  of  the  coronoid  process  is  much  more  easily 
determined.  The  palpating  finger  inserted  in  the  oral 
cavity  easily  feels  the  mobility  of  the  fractured  fragments. 
As  the  articular  process  remains  intact,  no  deformity  of 
the  lower  jaw  occurs,  but  attempts  to  open  the  mouth 
cause  sharp  pains.  As  Rose  has  stated,  it  is  quite  possi- 
ble in  these  fractures  that  a  false  connective-tissue  union 
may  occasionally  result  similar  to  that  accompanying  frac- 
ture of  the  olecranon  and  the  patella  [jjseudo-artlirosis). 
This  is  due  to  the  fact  that  the  scalp  at  the  coronoid  pro- 
cess contains  the  tendons  of  the  temporal  muscle,  which 
being  poorly  supplied  with  blood,  do  not  favor  the  forma- 
tion of  callus. 

Treatment  of  fractures  of  the  lower  jaw  consists  of  two 
important  procedures.  Primarily  the  dislocated  part  must 
be  replaced,  and  secondarily  an  absolute  fixation  must 
be  secured  which  will  keep  the  fractured  surfaces  in  juxta- 
position and  immobile  for  a  long  time.  In  many  cases 
the  upper  jaw  serves  as  an  excellent  splint  for  a  temporary 
dressing;  for  by  fastening  the  lower  jaw  to  the  superior 
maxilla  the  teeth  are  forced  to  articulate  properly  with  each 


*^^ 


Fig.  63. 


FRACTURES  OF  THE  LOWER  AND    UPPER  JAWS.   151 

other,  and  the  fractured  fragments  are  held  in  their  normal 
positions.  The  icire  splint  of  Sauer,  which,  being  applied 
and  fastened  to  the  sound  teeth,  acts  as  an  excellent 
further  dressing.  The  tooth  splint  recommended  by  the 
same  author,  consisting  of  two  parts,  is  often  more  satis- 
factory. The  upper  illustration  of  Fig.  63  shows  the  two 
parts  of  the  splint,  and  the  lower  illustration  shows  them 
united  7/i6«7j(.  This  tooth  splint,  however,  has  the  disad- 
vantage that  it  must  be  fastened  to  the  teeth  with  a  connec- 
tive wire,  which  often  causes  them  to  become  loose  ;  but  this 
disadvantage  may  be  overcome  by  employing  the  tooth 
si)lint  of  Weber,  which  is  made  of  vulcanized  India-rubber. 
This  Tiidia-rubbei'  splint  has  been  considerably  improved 
by  Haun  through  the  combination  of  rubber  and  gutta- 
percha. His  apparatus,  employed  with  good  results  in  the 
War  of  1866,  is  applied  as  follows  : 

After  the  jaw  has  been  replaced  to  its  normal  position 
by  means  of  digital  pressure,  the  rows  of  teeth  are  cov- 
ered with  a  layer  of  vulcanized  India-rubber,  removing 
enough  from  the  surface  to  permit  the  crowns  of  the 
teeth  to  perforate  it.  Another  layer  of  gutta-percha, 
softened  bv  heat,  is  then  placed  in  the  sphnt,  which  is 
forced  upon  the  teeth  of  the  fractured  jaw  as  rapidly  as 
])()ssible.  The  patient  is  then  requested  to  close  his 
mouth.  After  the  gutta-percha  has  become  hardened  the 
splint  usually  lies  tightly  in  place,  and  the  gutta-percha 
which  has  been  squeezed  out  shows  the  pressure  of  the 
antagonistic  tooth.  In  this  method  even  the  most 
severely  injured  were  soon  able  to  chew. 

However  convenient  it  may  be  to  prepare  and  wear  an 
India-rubber  splint,  its  porous  nature  favors  the  develop- 
ment of  degenerative  processes,  and  therefore  Port 
recommends  its  substitution  by  aseptic,  chemically  pure  tin. 

The  manner  of  applying  splints  for  fractures  of  the 
jaw  varies  for  each  case,  and  according  to  the  form  of  the 
apjwratus  employed.  In  general,  however,  one  should 
attempt  to  secure  a  good  impression,  wliether  India-rub- 
ber, tin,  or  wire  splints  are  em])loyed.  If,  while  the  im- 
pression is  being  taken,  the  fragments  become  displaced, 


152  FRACTURES  OF  THE  LOWER  AND    UPPER  JAWS. 

it  does  not  necessarily  mean  an  absolute  failure.  The 
plaster-of-Paris  model  is  simply  divided  at  the  involved 
portion,  and  the  parts  again  so  united  that  the  normal 
curvature  of  the  jaw  bone  is  obtained.  The  apparatus  is 
then  prepared  so  as  to  fit  exactly  this  model.  The  wire 
splint  is  fastened  with  soft  florist's  wire,  and  the  India- 
rubber  splint  is  fixed  with  gutta-percha. 

It  occasionally  becomes  necessary  to  treat  a  badly 
united  fracture  of  the  lower  jaw,  the  fragments  of  which 
were  displaced.  Suersen  applies  a  cap  to  each  part,  and 
pries  them  gradually  into  proper  position  by  pressing  a 
hickory  peg  between  them.  Best  results,  however,  are 
obtained  in  these  cases  by  the  application  of  a  properly 
constructed  regulation  apparatus. 

The  after-treatment  consists  simply  in  thorough  cleansing 
and  disinfection  of  the  oral  cavity,  for  septic  processes 
are  likely  to  arise,  especially  when  a  considerable  portion 
of  the  soft  tissue  is  injured.  With  our  modern  methods 
this  disinfection  is  easily  carried  out.  Formerly,  when 
another  external  apparatus  was  employed  to  fix  the  lower 
jaw  against  tlie  upper,  this  was  much  more  difficult  or  in 
fact  impossible.  It  was  not  only  impossible  properly  to 
nourish  the  patient  when  the  mouth  was  constantly  kept 
closed,  but  it  was  also  impossible  to  keep  the  oral  cavity 
clean,  and  therefore  this  method  has  gone  out  of  use. 

Fractures  of  the  upper  jaw  are  much  less  frequent  than 
those  of  the  lower  jaw.  This  is  probably  due  to  the  fact 
that  it  is  less  exposed,  and  is  better  protected  by  the  soft 
parts.  The  body  of  the  superior  maxilla  itself  is  rarely 
fractured,  while  the  zygomatic  and  alveolar  processes  are 
broken  more  frequently. 

Fractures  of  the  body  of  the  upper  jaw  occur  chiefly  as 
a  result  of  considerable  violence,  and  therefore  are  often 
accompanied  by  injury  to  the  soft  tissues  and  fracture  of 
the  base  of  the  skull ;  they  belong  really  to  the  sphere  of 
surgery. 

Of  more  importance  to  dentists  are  the  fractures  in 
the  region  of  the  alveolar  processes,  which  occur  quite  fre- 
quently in  the  extraction  of  teeth  from,  the  bicuspid  and 


FRACTURES  OF  THE  LOWER  AND    UPPER  JAWS.   153 

molar  portion  of  the  jaw,  where  the  walls  are  quite  thin. 
The  writer  has  treated  numerous  cases  of  fracture  of  the 
alveolar  processes,  and  here  presents  three  of  the  most 
typical  and  instructive  cases,  rather  than  give  a  descrip- 
tion of  the  various  conditions  that  might  occur. 

In  the  first  case,  an  attempt  to  extract  the  second  upper 
molar  of  a  young  man  was  accompanied  by  the  breaking 
off  of  so  large  a  piece  of  the  bone  that  the  antrum  was 
widely  exposed.  When  the  patient  presented  himself 
there  was  an  abundant  discharge  of  pus  from  the  sujjerior 
maxillary  sinus.  By  antiseptic  irrigations  the  inflamma- 
tion was  soon  overcome,  and  in  a  short  time  the  wound 
healed  over  with  scar  tissue. 

Less  common  is  the  second  case,  in  which  the  patient, 
a  man  forty  years  of  age,  having  been  stupefied  by  the 
escape  of  coal  gas,  fell  and  struck  his  face  on  a  foot  stool. 
As  a  result  the  alveolar  process  was  fractured  and  dislo- 
cated in  such  a  manner  that  the  four  upper  incisors,  upon 
closing  the  mouth,  rested  back  of  the  incisor  teeth  of  the 
louver  jaw.  The  jaw  fragments  Avere  first  replaced,  and 
then  a  gold  plate  was  made  for  the  patient,  which  forced 
the  incisors  somewhat  forward,  so  that  the  lower  teeth 
were  no  longer  able  to  strike  them.  By  being  thus 
placed  in  absolute  rest  the  jaw  healed  in  three  weeks. 

In  the  third  case,  a  powerful  blacksmith  was  struck  on 
the  neck  by  a  heavy  piece  of  iron  in  such  a  manner  that 
he  was  forced  face  downward  to  the  ground.  Inspection 
of  the  oral  cavity  disclosed  a  fracture  of  the  right  alve- 
olar process  of  the  upper  jaw.  Externally  the  line  of 
fracture  could  be  traced  from  the  cuspid  tooth  to  the  zygo- 
matic fossa  and  second  molar  tooth,  and  internally  it  ran 
close  to  the  raphe  of  the  hard  palate.  As  the  ])atient  did 
not  come  for  treatment  until  after  the  callus  had  begun 
to  form,  we  were  unable  with  the  usual  methods  to 
replace  the  bony  fragments,  which  were  already  consider- 
ably displaced.  Therefore,  a  palatine  plate  was  fixed  to 
the  sound  side,  which,  exerting  pressure  through  a  gold 
spring  upon  the  injured  teeth,  reduced  the  dislocation  in 
four  weeks. 


154 


DISLOCATION  OF   THE  LOWER  JAW. 


In  these  short  case  histories,  the  most  useful  methods 
of  treatment  are  described.  Much  of  what  has  been  said 
in  connection  with  the  lower  jaw  also  holds  true  for  the 
upper  jaw. 

DISLOCATION  OF  THE  LOWER  JAW. 

Luxation  of  the  inferior  maxilla  occurs  most  frequently 
forward.  It  usually  aifects  both  sides,  but  may  occur 
more  rarely  only  on  one  side.  The  articulating  head  of 
the  bone  is  displaced  forward  in  front  of  the  articular 
tubercle,  and  on  account  of  the  contraction  of  the  mus- 
cles of  mastication  is  unable  to  slide  back  into  the  socket 


Fig.  64— Reposition  of  a  dislocated  lower  jaw. 

of  its  own  accord.  Tearing  of  the  capsular,  the  internal 
lateral,  or  the  stylomaxillary  ligament  has  not  as  yet  been 
reported  ;  yet  it  is  not  difficult  to  imagine  how  such  com- 
plications may  occasionally  follow  severe  traumatism. 

The  causes  of  luxation  are  usually  similar  to  those  of 
fracture  of  the  lower  jaw  bone.  A  fall  or  a  blow,  as  well 
as  extraction  of  teeth,  may  result  in  such  an  injury. 
Forcible  opening  of  the  mouth  in  which  the  articulating 


EMPYEMA    OF  THE  ANTRUM  OF  HIGHMORE.  155 

head  glides  on  the  articular  tubercle  may  also  lead  to 
luxation.  Much  force  is  not  always  necessary  to  cause  a 
dislocation,  for  in  some  people  who  have  poorly  developed 
jaw  bones  or  thin  muscles  of  mastication,  the  lower  jaw 
becomes  habitually  displaced  on  the  slightest  provocation. 

The  treatment  of  this  form  of  dislocation  usually  pre- 
sents no  difficulty.  The  head  of  the  patient  is  held  by 
an  assistant,  and  the  jaw  is  grasped  with  both  hands  in 
such  a  manner  that  the  thumbs  rest  upon  the  molar  teeth 
while  the  remaining  fingers  clasp  the  bone.  Strong 
pressure  is  then  exerted  downward  and  backward,  caus- 
ing the  articulating  head  to  glide  back  over  the  articular 
tubercle  into  its  socket.  In  order  to  prevent  the  thumb 
from  being  bitten  by  the  too  rapid  replacement  of  the 
jaw  it  should  be  protected  with  a  napkin.  In  strong 
people  it  becomes  necessary  on  rare  occasions  to  reduce 
the  dislocation  under  chloroform  narcosis,  which  causes 
the  muscular  contracture  to  disappear. 

It  is  advisable  after  the  bone  has  been  replaced  to  sup- 
port it  for  a  time  with  a  bandage,  and  to  give  the  patient 
nothing  but  liquid  diet;  for  at  the  beginning  the  dis- 
location recurs  quite  frequently  when  the  mouth  is 
opened.  Persons  subject  to  habitual  dislocation  usually 
reduce  it  themselves  by  a  blow  on  the  chin  or  by  pressure 
upon  the  masseter  muscles,  von  Genzmer  recommends 
inunction  of  the  tincture  of  iodin  into  the  relaxed  artic- 
ular capsule. 

EMPYEMA  OF  THE  ANTRUM  OF  HIGHMORE. 

Empyema  is  the  most  frequent  affection  of  the  antrum 
of  Highmore.  It  consists  in  a  collection  of  pus  brought 
on  by  inflammatory  processes  in  the  mucous  membrane 
lining  this  cavity.  Disturbances  in  secretion  (hydrops)  are 
also  reported  to  have  been  developed  by  closure  of  the 
ostium  maxillare  either  as  a  congenital  defect  or  from 
disease.  As  a  result,  the  quantity  of  the  secretion  from 
the  mucous  glands  finally  l)ecomes  so  great  that  the 
pressure  resulting  in  the  antrum  leads  to  pain.     It  can- 


156  EMPYEMA  OF  THE  ANTRUM  OF  EIGHMOUE. 

not  be  denied  that  hydrops  probably  occurs  in  rare  cases, 
yet  it  is  at  any  rate  frequently  mistaken  for  cysts  which 
have  penetrated  into  a  sinus  of  the  superior  maxilla,  and 
which  on  perforation  discharges  a  more  or  less  clear  fluid. 

The  development  of  empyema  of  the  antrum  of  High- 
more  depends  upon  a  variety  of  factors  :  Inflammations 
may  extend  from  the  nasal  cavity  to  the  antrum,  or  in 
rare  cases  the  antrum  becomes  secondarily  involved  as  a 
sequel  to  empyema  of  other  air-containing  cavities,  as 
the  frontal  and  sphenoidal  sinuses.  The  possibility  of 
this  occurrence  may  be  easily  understood  by  studying  the 
metallic  casts,  in  Plate  3,  of  the  air-containing  cavities 
of  the  face,  which  show  the  relationship  of  these  various 
hollow  spaces  to  each  other. 

Foreign  bodies  may  be  the  etiologic  factors.  These 
occasionally  include  bullets,  knife  points,  and  even  roots  of 
teeth,  which,  during  extraction,  slipped  from  the  forceps 
and  entered  this  cavity.  Further  destructive  process  of 
the  alveolar  process  may  lead  to  suppuration  of  this  sinus ; 
but  in  the  majority  of  cases  the  teeth  themselves  are  the 
cause  of  the  empyema.  By  studying  Fig.  22  and  Plate  3, 
in  which  the  relationship  with  surrounding  structures  is 
accurately  portrayed,  it  will  be  observed  that  of  all  the 
teeth  the  first  and  second  molars  stand  in  closest  con- 
nection with  this  cavity.  Both  of  these  teeth  are 
implanted  directly  underneath  the  floor  of  the  antrum. 
In  rare  cases  also  the  roots  of  the  wisdom  and  second 
bicuspid,  as  well  as  abnormally  developed  roots  of  other 
teeth,  reach  close  to  this  sinus. 

The  dental  cause  is  to  us  the  most  important  one.  The 
disease  process  is  believed  to  extend  from  the  affected 
tooth  to  the  lining  membrane  of  the  superior  maxillary 
sinus.  If  we  consider  the  topographic  location  of  the 
upper  molars,  it  is  easily  understood  how  periodontic 
disease  may  spread  to  the  antrum.  The  apices  of  the 
roots  of  these  teeth  are  separated  from  the  floor  of  the 
antrum  of  Highmore  by  only  a  relatively  thin  bony  layer, 
and  if  the  antrum  of  a  macerated  skull  be  opened  with  a 
chisel,  little  cup-like  projections  will  be  observed  in  the 


EMPYEMA   OF  THE  ANTRUM  OF  HIGHMORE.   157 

floor,  caused  by  the  projections  of  the  alveoli  in  which 
the  roots  of  the  molar  teeth  are  set.  Hence  the  teeth 
stand  in  close  relationship  here  with  the  superior  maxil- 
lary sinus,  and  especially  so  when  the  alveolar  cups  and 
the  roots  arising  in  the  antrum  are  covered  with  almost 
nothing  but  soft  tissues. 

We  know  that  inflammatory  processes  of  the  periosteum 
may  easily  destroy  it,  and  as  a  consequence,  the  substance 
of  the  bone.  Hence  it  is  not  strange  that  inflammatory 
affections  of  the  upper  molars  lead  to  perforation  of  the 
antrum.  With  the  development  of  this  perforation, 
together  with  the  destruction  of  the  living  bony  layer, 
the  affection  has  easy  access  to  the  sinus.  It  does  not 
necessarily  follow,  however,  that  this  infection  must  lead 
to  an  empyema,  for  there  is  abundant  postmortem  evi- 
dence that  suppurating  apices  of  roots  have  perforated 
the  antrum  without  causing  empyema.  Why  the  same 
factor  should  cause  an  empyema  at  one  time  and  not  at 
another  is  not  very  clear.  The  most  plausible  explanation 
seems  to  be  that  in  one  case  the  vital  energy  of  the  superior 
maxilla  is  able  to  resist  the  attacking  micro-organisms 
and  not  in  another.  The  pathogeny  of  the  micro- 
organism also  undoubtedly  plays  an  important  part. 

Baume  believes  that  the  more  minute  processes  consist 
in  a  rarefaction  Avhich,  after  the  development  of  a  peri- 
odontitis, involves  the  floor  of  the  alveoli.  Primarily 
onlv  the  Haversian  canals  are  dilated,  then  the  bony 
lamellse  become  constantly  more  porous  until  they  finally 
disappear,  thus  permitting  the  pns  to  enter  the  antrum. 
Aside  from  this  form  of  perforation,  I  have  seen  two 
other  varieties.  Destruction  of  the  periodontium,  prob- 
ably through  the  influence  of  specific  bacteria,  may  lead 
to  a  real  necrosis  of  the  bony  plate.  The  latter  undergoes 
suppuration,  and  in  time  develops  a  large  opening  into 
the  cavity.  The  sequestra  are  friable  and  show  all  the 
characteristics  of  necrotic  bone.  This  form  of  perforation 
is  seen  more  frequently  after  extraction  than  after  a  peri- 
odontitis, and  may,  therefore,  accompany  slight  and 
apparently   insignificant  fractures  of  the  alveoli.      The 


158   EMPYEMA  OF  THE  ANTRUM  OF  HIGHMORE. 

second  form,  which  is  more  frequent,  consists  in  the  for- 
mation of  granulation  tissue  in  the  neighborhood  of  a 
diseased  molar  root.  This  progresses  without  inter- 
ruption into  the  bony  tissue,  from  which  it  extracts  the 
calcium  salts,  so  that  only  the  Sharpey's  fibers  remains. 
These,  too,  soon  disappear,  and  in  time  the  bony  tissue  is 
completely  substituted  by  the  round  cells  of  the  granu- 
lation tissue.  Finally,  the  mucous  membrane  of  the 
superior  maxillary  sinus,  which  has  thus  far  remained 
intact,  also  becomes  intergrown  with  granulation  tissue, 
and  an  ulcerated  area  is  formed  on  the  floor  of  the  antrum. 

At  first,  the  symptoms  which  accompany  this  disease  are 
not  prominent.  They  consist  of  pains,  distension  of  the 
antrum,  and  the  discharge  of  a  foul  smelling  pus  from  the 
nose.  The  pains,  however,  are  not  constantly  present. 
Patients  sometimes  are  afflicted  for  a  number  of  years  with 
empyema,  and  yet  experience  no  pain.  Some  patients  com- 
plain of  a  feeling  of  pressure  or  weight  within  the  upper 
jaw,  and  only  occasionally  suffer  sufficiently  from  pain  to 
consult  a  physician.  The  second  l)ranch  of  the  trigeminal 
nerve,  the  branches  of  which  run  in  thin  canals  within  the 
walls  of  the  antrum,  is  the  most  frequently  affected.  How- 
ever, the  first  branch  of  this  nerve  is  also  quite  frequently 
involved,  which  causes  the  pains  to  radiate  to  the  teeth. 
If  such  cases  are  not  carefully  examined,  one  is  likely  to 
diagnose  the  condition  as  trigeminal  neuralgia.  Pain  is 
more  frequently  an  accompaniment  of  the  acute  than  of 
the  chronic  condition. 

Of  the  walls  of  the  antrum,  the  thin  ones  are  naturally 
the  first  to  distend,  and  hence  the  nasal  wall  bulges  before 
the  others.  However,  as  this  wall  is  hidden,  its  condition 
often  escapes  detection,  and  hence  iu  literature,  the  facial 
wall  is  usually  stated  as  being  the  first  to  bulge  in  empy- 
ema. In  severe  cases  the  patients  themselves  note  that 
one  nasal  orifice  is  obstructed,  and  examination  will 
usually  show  that  the  bulging  nasal  wall  of  the  antrum, 
together  with  secondary  swelling  of  the  nasal  mucous 
membrane,  has  completely  closed  one  nostril.  Bulging 
of  the  facial  wall  is  more  readily  recognized,  and  is  some- 


E3IPYEMA  OF  THE  ANTRUM  OF  SIGHMORE.   159 

times  associated  with  reddening  and  edema  of  the  cheek. 
If  the  bone  has  become  very  thin  through  loss  of  sub- 
stance, pressure  may  elicit  crepitation,  the  bone  may  even 
undergo  perforation  with  the  formation  of  a  fistula.  If 
the  orbital  roof  bulges,  exophthalmos  may  occur,  yet  in 
this  case  the  eye  is  only  slightly  forced  out.  If,  however, 
cellulitis  should  develop  in  the  retrobulbar  space,  a  high 
grade  exophthalmos  ^vlll  result.  Even  the  roof  of  the 
hard  palate  bulges  occasionally,  but  usually  not  until  the 
remainder  of  the  antrum  is  considerably  distended,  the 
deformity  being  easily  detected  in  the  mouth.  This  dis- 
tension results  from  a  periostitis  and  an  osteomyelitis, 
which  cause  the  bony  substance  to  soften  and  become 
thin.  However,  the  engorgement  of  the  secretion,  which 
follows  closure  of  the  ostium  maxillare,  is  often  sufficient 
to  account  for  the  distension. 

The  third  symptom,  the  discharge  of  pus  from  the  nose, 
is  rarely  absent.  The  patients  usually  state  that  they 
occasionally  taste  the  pus  in  the  mouth  upon  awakening 
in  the  morning,  and  a  foul  odor  may  be  detected  issuing 
from  the  nose.  The  discharge  of  pus  from  the  nose  is 
easily  explained.  When  the  patient  lies  upon  the  healthy 
side,  the  contents  of  the  antrum  of  Highmore  empty 
into  the  nose  either  through  the  ostium  maxillare  or 
through  accessory  openings,  which  may  also  connect 
the  superior  maxillary  sinus  with  the  nasal  cavity.  The 
contents  consist  of  a  slimy  pus,  which,  however,  does  not 
flow  easily,  because  the  high  position  of  the  ostium  maxil- 
lare causes  it  to  stagnate  in  the  antrum  and  then  become 
thickened.  This  stagnation  does  not  only  cause  it  to 
become  thick  and  tenaceous,  but  gives  it  the  characteristic 
sweetish  odor  with  which  all  practitioners  are  acquainted. 
Under  these  circumstances  it  is  natural  for  fever  to  set  in. 

The  freat)nenf  of  the  empyema — that  is,  of  the  causal 
conditions — is  under  all  circumstances  imperative,  for 
not  only  the  above  described  symptoms  of  more  or  less 
severity  are  concerned,  but  the  possil)ility  of  a  fatal  ter- 
mination, must  also  be  considered.  This  may  follow 
general  sepsis,  or  be  caused  by  meningitis,  the  cousidera- 


160  EMPYEMA  OF  THE  ANTRUM  OF  HIQHMOEE. 

tion  of  which  must  not  be  excluded.  The  development 
of  the  latter  may  be  easily  understood  by  examining  the 
corrosion  preparation  in  Plate  3,  which  shows  the  close 
relationship  existing  between  the  retrobulbar  space  and 
the  superior  maxillary  sinus.  The  cast  of  the  inter- 
vaginal  space  of  the  optic  sheath  alone  presents  a  direct 
path  for  the  transmission  of  pyemic  processes  to  the  hard 
and  soft  cerebral  meninges. 

It  is  important  above  all  things  that  the  pus  be 
permitted  to  discharge  freely.  This  may  be  done  by 
perforating  the  antrum  at  any  point.  The  following 
areas  for  perforation  are  preferred  :  The  lower  portion  of 
the  nasal  wall  ( Hunter  )  ;  the  facial  wall  (  Dessault ) ; 
the  hard  palate,  the  alveolar  process  (Cooper). 

Securing  an  entrance  from  the  nasal  wall  is  recommended 
as  being  the  most  convenient,  because  here  the  natural 
connection  between  the  superior  maxillary  sinus  and  nasal 
cavity  may  be  employed.  This  is,  however,  a  false 
premise  ;  on  the  contrary,  it  is  exceptionally  difficult  to 
pass  a  sound  through  the  ostium  maxillare,  for  it  is  hidden 
in  the  anterior  lateral  portion  of  the  hiatus  semilunaris. 
Because  of  the  difficulty  in  finding  this  entrance,  Zucker- 
kandl  recommends  piercing  the  wall  at  its  thinnest  por- 
tion, that  is,  in  the  middle  meatus,  with  a  trochar.  Partsch 
objects  to  this  method,  and  justly  so,  because  the  anatomic 
do  not  correspond  to  the  clinical  conditions ;  for  if  it  be 
possible,  the  pus  should  be  permitted  to  flow  at  the  lower- 
most point  of  the  cavity.  Therefore,  Mikulicz  overcomes 
this  objection  by  piercing  the  nasal  wall  at  its  lower  portion. 

Piercing  the  antrum  of  Highmore  from  the  facial  sur- 
face, or  through  the  hard  j)((^(de,  is  frequently  recom- 
mended. The  latter  offers  no  special  advantage,  and  on 
account  of  the  thickness  of  the  bone  it  is  performed  with 
difficulty.  The  former  is  useful  when  a  large  portion  of 
the  antrum  wall  has  been  removed,  and  when  it  is  desired 
to  give  the  palpating  finger  easy  access  to  its  interior. 

Perforation  of  the  alveolar  process  is  preferred  by 
dentists  as  being  the  most  advantageous.  If  the  molars 
are  absent,  an  atrophic  condition  is  nearly  always  present, 


EMPYEMA  OF  THE  ANTRUM  OF  HIGHMORE.   161 

and  as  a  result  the  bone  consists  of  a  thin  compact  portion 
with  few  spongiose  trabecuhe,  which  may  be  easily  punc- 
tured with  a  trochar.  If,  however,  defective  teeth  should 
be  present,  they  may  be  removed  without  hesitation — an 
operation  which  will  give  considerable  assistance  in  reach- 
ing the  goal.  A  pointed  instrument  is  then  forced  with 
a  twisting  motion  through  the  alveolus  into  the  antrum. 
It  is  equally  favorable  whether  the  first  or  second  molar 
tooth  be  selected  ;  but  it  must  be  remembered  that  if  the 
puncture  be  made  through  the  first  molar,  the  concavity 
below  the  zygomatic  process  and  also  the  soft  tissues  of 
the  cheek  may  be  pierced.  Therefore,  when  the  instrument 
is  passed  through  the  alveolus  of  a  buccal  root,  it  should 
be  directed  slightly  inward  toward  the  palate  ;  but  if  the 
alveolus  of  a  palatine  root  be  selected,  the  instrument 
should  be  directed  straight  u[)\vard.  AYhen  the  alveolus 
of  the  second  molar  tooth  is  selected,  there  is  danger  of 
forcing  the  instrument  in  front  of  the  maxillary  tuberosity. 
Therefore,  it  must  not  be  forgotten  to  direct  the  puncture 
toward  the  inner  canthus  of  the  eye. 

Aside  from  the  ease  with  which  the  antrum  is  punctured 
from  tlie  alveolar  process,  it  offers  the  additional  advan- 
tage of  opening  the  cavity  at  its  lowermost  point,  and 
thus  permitting  all  the  pus  to  escape.  The  patient  may 
also  be  able,  when  the  puncture  is  made  in  this  region,  to 
wash  out  the  antrum  himself,  in  the  manner  ordered  by  a 
physician. 

Immediately  after  the  opening  of  the  antrum,  it  should 
be  washed  out  in  order  to  give  the  patient  relief,  which 
will  not  occur  until  the  pus  has  been  discharged.  This 
operation  may  be  easily  carried  out  by  using  an  instru- 
ment, in  making  the  perforation,  which  is  of  the  same  size 
as  the  canula  of  the  syringe  (for  example  6  mm.).  Thus 
the  canula  will  fit  well  into  the  opening,  which  is  of 
importance  when  it  is  desirous  to  exert  a  certain  amount  of 
pressure,  as  in  case  of  a  narrow  ostium  maxillare  or  thick 
pus.  There  is  no  indication  for  the  employment  of  an 
antiseptic  solution  ;  on  the  contrary  it  suffices  simply  to 
fill  the  syringe  with  sterile  water  slightly  heated.  Dur- 
11 


162  EMPYEMA   OF  THE  ANTRUM  OF  HlGHMOBE. 


6  mm. 


ing  the  process  the  head  should  be  bent  forward.  At  the 
beginning  a  more  or  less  viscid  mass,  according  to  the 
character  of  the  collected  secretion,  flows  from  the  nose. 
The  more  frequently  the  injections  are  repeated,  the  less 
turpid  will  be  the  water,  until  finally  it  flows  from  the 
nose  absolutely  clear. 

It  is  as  injudicious  to  let  the  wound  alone  as  it  is  to 
insert  a  drainage  tube.  In  the  first  case  granulation  takes 
place,  which  closes  the  opening,  so  that  eventually  it 
becomes  necessary  to  make  another  perforation.  Although 
the  drainage  tube  permits  the  outflow  of  the  secretion,  it 
also  carries  infection  into  the  antrum.  The  best  method, 
therefore,  and  one  employed  by  many 
practitioners,  consists  in  inserting  a  prop- 
erly fitting  stopper  into  the  perforated 
opening  (see  Fig.  65).  This  little  instru- 
ment should  have  the  same  diameter  (6  mm.) 
as  the  wound.  Since  the  granulation  tissue 
within  the  antrum  soon  grows  upward 
around  the  stopper,  it  should  be  given  a 
sufficient  length,  that  is,  about  2.5  cm.; 
and  in  order  to  prevent  it  from  slipping 
upward,  a  small  plate  is  fastened  at  its  base. 
Partsch  constructed  a  drainage  tube  with 
valves  which  was  very  effective,  but  a  solid 
stopper  is  more  eff'ectual  than  an  India- 
rubber  valve  in  preventing  the  entrance  of  food.  Less 
important  than  the  form  is  the  material  from  which  this 
little  obdurator  is  constructed.  For  this  purpose  hard 
rubber  may  be  employed,  which  is  joined  to  a  dental 
plate ;  equally  as  useful  are  aluminum,  silver,  gold,  etc. 

The  affer-treatment,  if  the  above  procedure  has  been 
carried  out,  is  very  simple.  The  day  following  the  oper- 
ation the  antrum  is  washed  out  ^A^th  warm  distilled  water 
injected  through  the  perforation.  If  the  water  reappears 
clear,  it  may  be  expected  that  the  process  will  heal  with- 
out any  further  trouble.  In  most  cases,  however,  the 
water  remains  turpid,  and  it  will  be  necessary  to  attack 
the  condition  with  antiseptic  solutions.     For  this   pur- 


FiG.  65.— A  stop- 
per for  closin^the 
perforation  into 
the  antrum  of 
Highmore.  Nat- 
ural size. 


ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE.   163 

pose  a  very  weak  solution  of  hydrogen  peroxid  is  useful, 
as  are  also  solutions  of  the  sublimate  of  mercury,  boric 
acid,  etc.  Insufflation  of  iodoform  into  the  antrum  has 
also  been  attempted,  and  Baume  recommends  washing 
with  a  glass  of  water  containing  a  half  teaspoonful  of 
tannin. 

In  spite  of  the  employment  of  these  various  remedies, 
all  of  which  are  equally  good,  healing  may  sometimes  be 
prolonged  for  weeks,  months,  and  even  years.  In  chronic 
cases,  at  any  rate,  one  has  the  satisfaction  of  having 
relieved  the  patient  of  the  pressure,  so  long  as  he  follows 
the  instructions  and  washes  out  the  antrum  daily.  Cessa- 
tion in  the  excretion  of  the  pus  after  a  period  of  time 
does  not  necessarily  imply  that  the  empyema  has  been 
cured.  Therefore,  the  stopper  should  not  be  removed 
and  the  wound  permitted  to  heal  until  there  has  been  no 
recurrence  after  a  considerable  length  of  time. 


ACQUIRED  AND  CONGENITAL  DEFECTS 
OF  THE  FACE. 

The  acquired  defects  of  the  face  interest  the  dentist  only 
Avhen  they  involve  the  hard  and  soft  palate  and  the  alve- 
olar process.  In  rare  cases  they  are  due  to  mechanical 
influences,  as  from  a  shot  or  a  blow  with  a  sharp  or  dull 
instrument  passed  into  the  mouth.  Communicating  open- 
ings between  the  oral  and  the  nasal  cavities  occur,  how- 
ever, more  frequently  as  the  result  of  disease  processes 
like  syphilis  and  tuberculosis.  Of  these,  syphilitic  ulcer- 
ations are  the  most  frequent,  because  tuberculosis  of  the 
mouth  is  less  common  than  lues.  In  tuberculosis  defects 
of  the  jaws  are  nearly  always  the  sequels  of  facial  lupus. 

As  either  wounds  or  fissures  with  ulcerating  edges 
accompany  acquired  defects,  the  diagnosis  is  easily  made. 

The  treatment  of  acquired  defects,  as  a  rule,  does  not 
differ  from  that  of  congenital  defects,  and  therefore  a  sep- 
arate therapv  need  not  be  given.  An  exception  is  the 
luetic  defect  which,  being  sometimes  quite  extensive,  may 


164  ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE. 

FIGURE  66. 

Upper  illustration. — Front  view  of  a  four-weeks  old  embryo,  a. 
Ej^es.  6.  Lateral  nasal  process,  c.  Middle  nasal  process,  with  the  two  globu- 
lar processes,  d.  Maxillary  process,  e.  First  branchial  arch.  /.  This  line 
points  to  the  region  of  the  olfactory  pit.  The  red  line  indicates  the  Y- 
shaped  fissure. 

Lower  illustration. — Face  with  a  diagrammatic  presentation  (red) 
of  fissure  formation,  m.  Process  of  the  lateral  nasal  fissure,  which 
begins  on  the  upper  lip,  at  the  point  of  predilection  for  hare-lip,  and 
which  extends  toward  the  nasal  opening,  and  sometimes  even  to  the 
inner  canthus  of  the  eye.  It  results  from  failure  of  the  proper  closing 
of  the  middle  (a)  and  lateral  (d)  nasal  processes,  i.  Oblique  fissure  of  the 
face  lying  between  the  lateral  nasal  process  (d)  and  the  maxillary  process 
(c).  h.  Transverse  fissure  of  the  face  lying  between  the  maxillary  pro- 
cess ic)  and  the  first  branchial  arch  (6).  t.  Median  fissure  of  the  superior 
maxilla  lying  between  the  two  globular  processes.  1.  Median  fissure  of 
thelowerjaw  between  the  leftaiid  right  branchial  arches. 

be  cured  through  the  constitutional  treatment  by  ruercuiy 
and  potassium  iodid. 

The  congenital  defects  of  the  face  can  only  be  understood 
by  acquiring  an  exact  knowledge  of  embryology,  for  they 
usually  result  from  failure  in  union  of  those  parts  of  the 
face  which  occur  in  pairs.  Secondary  separations  of 
already  united  parts  occur  very  rarely  and  are  due  to 
mechanical  or  pathologic  causes.  For  practical  reasons 
then  embryology  of  the  mouth  Avill  be  discussed  in  this  place. 

Bmbryologfy  of  the  Head. — The  head  is  distin- 
guishable in  an  embryo  when  it  has  reached  a  length  of 
7.5  mm.;  that  is,  in  the  fourth  week  of  intra-uterine  life. 
At  this  time  its  length  is  about  a  quarter  that  of  the  whole 
body.  The  midbrain  is  best  developed  at  this  stage  while 
the  diencephalon  and  the  prosencephalon,  which  lie  in  front 
of  it,  and  the  epencephalon  and  the  raetencephalon,  which 
lie  posteriorly,  are  as  yet  considerably  backward  in 
development.  From  Fig.  QQ  we  observe  that  the  eye  is 
located  underneath  the  diencephalon,  to  which  it  belongs 
because  of  its  origin.  The  olfactory  organ  lies  in  front 
of  the  eyes  at  the  lower  border  of  the  prosencephalon. 
This  is  at  first  indicated  by  a  lateral  depression,  sur- 
rounded by  a  crater-like  wall.  Passing  between  the  two 
portions  of  the  organ  of  smell  is  a  crest  which  is  of  great 
interest  to  dentists,  as  will  be  seen  in  the  description  of 
facial  defects  to  follow\     This  is  the  frontal  process,  also 


Fig.  66. 


ACQUIRED  ASD  CONGENITAL  DEFECTS  OF  FACE.   165 

called  the  middle  nasal  process,  to  either  side  of  which  lie 
the  two  lateral  nas(d  processes.  Lying  upon  the  epeii- 
cephalonoii  a  level  with  the  second  branchial  arch  is  a  pear- 
shaped  elevation,  the  so-called  auditory  organ,  the  thick 
end  of  which  lies  in  front,  while  the  smaller  end  is  directed 
backward.  It  lies  too  far  posteriorly  to  be  shown  in  the 
illustration.  The  four  branchial  or  fancied  arches  are 
presented  as  thick  swellings,  which  extend  considerably 
forward.  The  first  breinchied  arch  extends  the  furthest  for- 
ward, and  almost  reaches  the  olfactory  organ.  The  second 
is  also  well  developed,  biit  is  somewhat  shorter  than  the 
first.  Both  arches  are  corresjjondingly  lobulated  in  such 
a  manner  that  each  possesses  an  anterior  and  a  posterior 
lobe.  The  third  arcli,  although  mucii  reduced  in  size, 
shows  a  deep  lobulation  dividing  it  into  two  parts.  The 
fourth  arch  lies  below  the  cervical  prominence,  and  is  com- 
pletely covered  in  that  region  by  the  third  arch.  The  extent 
of  the  grooves  lying  between  the  branchial  arches  depends 
upon  the  length  of  the  corresponding  arch.  Accordingly, 
it  will  be  observed  that  the  first  groove,  which  lies  l)etween 
the  first  and  the  second  l^ranchial  arches,  is  very  long  ;  the 
second,  lying  between  the  second  and  third  branchial 
arches,  is  decidedly  shorter ;  the  third  and  fourth  grooves 
are  partially  hidden  within  and  are  still  shorter  than  the 
foregoing. 

The  question  arises,  what  is  formed  by  the  first  branchial 
or  faucial  arch  in  the  course  of  development  ?  The  first 
branchial  arch  forms  the  lower  jaw.  We  may  conclude  at 
once  that  the  whole  face,  that  is,  the  part  between  the 
mouth  and  forehead,  must  develop  from  the  exceedingly 
slirunkcn  portion  lying  between  the  first  branchial  arch 
and  tlie  prosencephalon.  The  fissure  in  front  of  the  first 
branchial  arch  may  be  designated  as  the  primitive  oral 
cleft.  In  the  upper  illustration  of  Fig.  QQ  is  seen  a  swollen 
])rojection  situated  l)ctween  the  first  branchial  arch  and  tlie 
frontal  region,  which  at  this  time  is  already  well  developed. 
This  is  tlie  superior  ma.villarii  process,  whieli  later  forms 
the  side  of  the  face.  On  one  side  it  touches  the  eye  and  on 
the  otiier  side  the  olfactory  pit.     It  lies,  therefore,  between 


166  ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE. 

these  organs,  and  projects  with  its  free  rounded  end  into  the 
primitive  oral  cleft. 

The  maxillary  process  forms  the  following  bones  :  the 
upper  jaw,  the  malar,  the  palate,  and  the  sphenoid.  The 
so-caWed  frontal  or  nasal  2J>'oc£ss  grows  obliquely  down- 
ward from  the  lower  surface  of  the  prosencephalon  in  a 
medial  direction  toward  the  oral  cleft.  The  surface  of 
this  frontal  process  is  not  smooth,  but  is  broken  by  a 
groove  on  both  sides  which  run  to  the  olfactory  pit  and 
to  the  eye.  These  grooves  divide  the  frontal  process  into 
a  median  and  a  lateral  frontal  or  nasal  process.  The 
median  broad  groove  {nasal  groove),  which  divides  the 
middle  nasal  process  into  two  parts,  creates  two  lobulated 
formations  by  joining  with  the  groove  that  divides  the 
middle  from  the  lateral  nasal  process.  These  lobular  for- 
mations project  into  the  oral  opening,  and  are  known  as  the 
globidar  jxrocesses. 

The  nasal  septum,  which  originally  consisted  of  two 
flaps  of  tissue  and  the  intermaxillary  bone  which  contains 
two  incisor  teeth  on  either  side,  arise  from  the  middle 
nasal  process.  The  lateral  nasal  processes  form  the  nose  ; 
that  is,  the  lateral  nasal  cartilages,  the  nasal  bone,  the  lach- 
rymal bone,  and  the  turbinate  process  of  the  ethmoid 
bone. 

These  various  bones  begin  to  grow  together  when  the 
embryo  has  reached  a  length  of  11  mm.,  that  is,  during 
the  fifth  week  of  fetal  life.  The  maxillary  processes  by 
growing  energetically  forAvard  toward  the  median  line, 
come  in  contact  with  the  median  nasal  process,  which  by 
this  time  has  also  developed  more  fully.  In  a  lateral 
direction  it  grows  around  the  eye.  On  the  other  hand, 
the  lateral  nasal  process  is  more  backward  in  development, 
and  becomes  compressed  into  a  narrow  space  which  lies 
between  the  eye,  the  frontal  crest,  median  nasal  process, 
and  maxillary  process.  The  middle  nasal  process  shows 
greater  development  at  the  sides  than  in  the  center. 
This  causes  an  indentation  which  is  of  significance  in  the 
later  development  of  the  face,  and  especially  of  the  nose. 
Gradually  the  embryotic  head  assumes  a  more  human 


ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE.  167 

form.  The  finer  modulation  takes  place  in  the  eighth 
week  ;  the  nasal  septum  becomes  narrower,  and  at  the 
same  time  higher,  which  causes  the  nose  to  become  ele- 
vated above  the  surface  of  the  face.  The  ears  grow 
slowly  upward,  the  eyes  pass  from  the  side  forward, 
toward  the  median  line.  The  chin  begins  to  project  and 
the  oral  cleft,  formerly  five-cornered,  becomes  a  simple 
slit.  The  median  notch  of  the  upper  lip  has  grown 
closed  and  the  formation  of  the  ^Ai/^?'i(m  begins  ;  the  latter 
is  the  superficial  groove  which  is  directed  downwards 
from  the  nasal  septum. 


Fig.  67.— Primitive  oral  cavity  (schematic):  a,  median  nasal  process  with 
(/)  the  globular  processes:  6,  first  branchial  arch;  c.  superior  maxillary  pro- 
cess ;  d,  lateral  nasal  process ;  e,  eye :  ri,  lateral  nasal  groove :  the  line  points 
toward  the  olfactory  pit :  /(,  lateral  groove  of  the  angle  of  the  mouth  ;  i,  oculo- 
nasal groove  ;  k,  median  cleft  of  the  first  branchial  arch. 


Aside  from  these  introductory  remarks  on  the  develop- 
ment of  the  face  we  have  still  to  consider  the  special  fin- 
mation  of  the  mouth  in  order  to  explain  the  jiathologic 
fissure  formations.  As  we  have  seen,  the  mouth  did  not 
originally  represent  a  simple  slit,  but  a  whole  series  of 
fissures  radiated  from  it,  which  have  been  obliterated  by 
the  accompanying  processes.  Fig.  67  represents  the 
primitive  oral  fi.ssures  schematically.  There  exist  at  this 
stage  five  grooves  :  1.  The  median  groove  {k)  of  the  mid- 


168  ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE. 

die  nasal  process,  short  but  yet  comparatively  wide.  2.  A 
second  somewhat  longer  but  narrower  groove,  the  so-called 
nasal  groove  (g),  occurring  in  pairs,  and  leading  from  the 
oral  cavity  to  the  olfactory  pit ;  on  the  median  side  it  is 
bordered  by  the  inner  nasal  process,  laterally  by  the  outer 
nasal  process,  and  below  by  the  maxillary  process,  at  the 
median  extremity  of  which  it  empties  into  the  oral  cavity. 
3.  The  oculonasal  groove  (i)  which  for  a  short  distance 
from  the  oral  cavity  begins  and  runs  in  common  with  the 
nasal  cleft,  extending  to  the  eye,  which  it  partially  sur- 
rounds. It  is  principally  bounded  by  the  lateral  nasal 
process  and  the  superior  maxillary  process. 

At  an  earlier  stage  it  lies  in  a  horizontal  plane,  but  in 
the  course  of  time  assumes  a  more  erect  position.  For 
practical  purposes  the  clefts  passing  to  the  olfactory  pit 
and  the  eye,  together  with  the  associated  processes  that 
project  into  the  oral  cavity,  are  referred  to  as  the  Y-shaped 
deft  (see  Fig.  66).  Between  the  two  upper  limbs  of  the 
Y  lies  the  lateral  nasal  process.  In  a  medial  direction 
from  the  short  limb  of  this  cleft  lies  what  has  been  termed 
the  globular  process  of  the  median  nasal  process,  and  in  a 
lateral  direction  the  superior  maxillary  process.  4.  A 
lateral  prolongation  of  the  oral  cleft  is  formed  by  the 
lateral  grooves  of  the  angles  of  the  mouth.  5.  Finally, 
at  the  median  line  of  the  first  branchial  arch  lies  a 
depression  exactly  opposite  the  median  groove  of  the 
middle  nasal  process  (c). 

Of  the  development  of  the  true  ojxil  cavity,  we  will 
consider  only  that  which  is  of  interest  in  connection  with 
the  formation  of  fissures  or  clefts.  The  roof  of  the  oral 
cavity  is  formed  by  the  maxillary  process  through  its 
palatine  plate,  which  gradually  joins  its  opposite  fellow 
in  the  median  line.  The  middle  nasal  process  passes 
from  in  front  between  these  plates,  and,  as  the  anterior 
and  lower  termination  of  the  nasal  septum,  forms  the 
intermaxillary  bone.  The  latter  leaves  a  small  opening 
on  either  side  where  it  joins  the  palatine  plate,  known  as 
the  foramen  incisivum.  The  upper  lip  is  formed  by  the 
union  of  the  two  globular  processes  with  the  intermaxil- 


ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE.  169 

lary  bone.  The  globular  processes  have  two  processes 
directed  backward,  which  gradually  approach  each  other, 
and  becoming  flattened,  form  two  vertical  opposing  plates. 
The  latter  grow  together  and  give  rise  to  the  cartilaginous 
portion  of  the  nasal  septum. 

After  the  above  description  the  explanation  of  the 
development  of  congenital  clefts  in  the  region  of  the 
mouth,  provided  they  are  typical  and  not  complicated 
by  other  pathologic  ])rocesse&,  should  present  no  great 
difficulties. 

The  most  frequent  cleft  is  that  which  results  in  con- 
sequence of  failure  in  union  of  the  Y-shaped  fissure,  as  is 
shown  in  the  upper  illustration  of  Fig.  66.  This  defect 
is  particularly  likely  to  occur  in  the  union  of  the  medial 
(see  also  Fig.  Ql  g)  and  the  lower  limbs.  The  lateral 
cleft  of  the  lip  (Fig.  66,  lower  illustration),  also  known  as 
hare-lip,  is  due  to  this  failure  in  union  of  the  medial  with 
the  lower  limb  of  the  Y-shaped  fissure.  It  indicates, 
therefore,  faulty  growth  of  the  middle  and  lateral  nasal 
processes,  and  as  a  result  the  lip  is  divided  into  two  parts 
in  the  region  between  the  lateral  incisor  and  the  cuspid 
tooth.  Hare-lip  is  commonly  one-sided,  but  if  it  occur 
on  both  sides,  the  middle  portion  of  the  lip,  together  with 
the  philtrum,  intermaxillary  bone,  and  nasal  septum  may 
project  to  a  less  or  greater  extent  beyond  the  plane  of  the 
face  as  the  so-called  rump  or  Bi'irzel.  Even  Goethe 
recognized  that  faulty  union  of  the  superior  and  inter- 
maxillary bones  led  to  the  formation  of  double  hare-lip. 
He  did  not,  however,  correctly  explain  the  origin  of  single 
hare-lip,  for  he  thought  it  to  be  due  to  imperfect  union 
of  both  maxillary  bones.  The  reason  for  this  mistake  is 
that  he  overlooked  the  lateral  position  of  the  hare-lip. 
He  had  evidently  imagined  it  to  be  in  the  middle  line  of 
the  upper  lip  where  it  occurs  only  in  very  rare  instances, 
and  then  in  consequence  of  improper  closure  of  the  median 
groove  of  the  mesial  nasal  process. 

Hare-lip,  instead  of  terminating  at  the  nasal  orifice, 
occasionally  extends  vertically  upward  as  the  lateral  nasal 
cleft  to  the  region  of  the  base  of  the  nose.      Analagous  to 


170  ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE. 

hare-lip  this  cleft  may  also  occur  on  both  sides,  in  which 
case  the  nose  projects  prominently  forward  supported  in 
back  only  by  the  septum.  Genetically  the  lateral  nasal 
fissure  is  due  to  improper  union  of  the  inner  line  of  the 
Y-shaped  cleft,  which  runs  to  the  olfactory  pit.  There- 
fore, the  mesial  nasal  process,  which  is  divided  by  the 
nasal  groove,  cannot  unite  with  the  lateral  nasal  process. 
The  oblique  facial  fissure  is  a  large  groove  which  begins 
at  the  hare-lip,  or  more  frequently  to  one  side  of  it,  and 
runs  obliquely  toward  the  eye  and  ends  in  the  lower  eye- 
lid as  a  coloboma.  Indeed,  it  may  even  in  severe  cases 
encircle  the  lower  portion  of  the  eye  and  reach  laterally 
to  the  ends  of  the  eyebrows.  This  oblique  facial  defect 
follows  imperfect  union  of  the  lateral  limb  of  the  Y-shaped 
cleft ;  that  is,  of  the  lateral  nasal  and  superior  maxil- 
lary processes,  and  represents  the  oculonasal  groove  (  Fig. 

67  i). 

If  the  space  between  the  first  branchial  arch  and  the 
superior  maxillary  process  remains  open,  the  transverse 
facial  fissure  results.  This  represents,  therefore,  a  per- 
sistency of  the  primitive  angle  of  the  mouth  (  see  Fig. 
76  h ).  An  evident  contradiction  to  this  statement  is  the 
fact  that  the  transverse  facial  cleft  forms  an  oblique 
arch  (  where  convexity  is  above )  in  its  course  toward  the 
ear  ;  for  the  auditory  germ  lies  much  lower  in  the  region 
of  the  second  branchial  arch.  This  direction  may,  indeed, 
be  first  understood  when  the  ear  is  raised  from  the  second 
to  the  first  branchial  arch. 

Cleft  formations  in  the  mesial  line  are  much  rarer  than 
those  of  the  lateral  grooves  ;  they  represent  a  splitting  of 
the  upper  jaw,  of  the  mesial  cleft  of  the  upper  lip  ;  that  is, 
the  formation  of  the  philtrum  is  retarded  and  in  its  place 
a  fossa  is  formed.  The  process  concerned  is  a  retar- 
dation in  the  ultimate  mesial  division  of  the  middle  nasal 
processes  ( Fig.  67  k ),  on  account  of  which  the  globular 
processes  cannot  unite.  In  fact  for  embryologic  reasons, 
this  cleft  can  never  stretch  out  beyond  the  base  of  the 
nose.  Still  in  severe  cases,  for  want  of  a  proper  base, 
the  development  of  the  nasal  tip  may  be  impossible  ;  in 


ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE.  171 

that  case  the  nasal  orifices  spread  far  apart  and  between 
them  is  stretched  a  flat,  often  a  concave^  area  of  skin. 

The  rarest  defect  is  due  to  failure  in  union  of  the  first 
two  branchial  arches,  on  account  of  which  a  mesial  cleft 
of  the  lower  lip  results. 

Of  most  interest  to  dentists  are  the  lateral  labial  or 
nasal  clefts.  These  may  be  confined  to  the  external  soft 
parts  or  they  may  extend  to  the  interior  of  the  oral  cavity. 
In  the  first  case  the  defect  is  a  hare-lip  ( labium  leporiuin\ 
and  in  the  second  a  cleft  palate  (^palatum  fissum  ).  Ac- 
cording to  the  location  the  following  nomenclature  has 
been  adopted  :  If  the  fissure  formation  does  not  extend 
beyond  the  limits  of  the  lip,  the  condition  is  called  cheilo- 
chisnia ;  this  is  the  true  hare-lip.  If  this  defect  be  com- 
plicated by  a  cleft  of  the  alveolar  process  of  the  upper 
jaw,  the  term  cheilognathocldsina  is  employed.  If  the 
abnormality  be  also  accompanied  by  division  of  the  soft 
palate,  the  condition  is  called  cheilognathouranochisma  ;  in 
this  case  the  whole  palate  is  split.  When  the  division  is 
but  ])artial  it  is  a  uranoco/oboma. 

Depending  upon  the  position  of  the  intermaxillary 
bone  ac/(;/if  of  the  palate  begins  between  the  lateral  incisor 
and  cuspid  teeth,  and  reaches  the  middle  line  only  after  it 
has  encircled  the  intermaxillary  bone.  This  cleft  estab- 
lishes a  communication  between  the  oral  and  the  nasal 
cavity.  In  the  case  of  double  cleft  palate  the  nasal 
septum  projects  independently  into  the  oral  cavity.  In 
addition  to  the  hard  palate  the  soft  palate  may  be  split, 
and  the  resulting  cleft  reach  so  far  back  that  the  uvula 
is  separated  into  two  parts;  and  indeed  the  uvula  as  well 
as  a  more  or  less  large  portion  of  the  velum  palati  may 
be  absent. 

From  a  clinical  point  of  view  the  facial  clefts  are  of 
great  importance,  because  of  their  disfigurement  and  their 
interference  with  speech.  Children  possessing  such 
'defects  have  a  much  higher  mortality  rate  than  normal. 
They  die  because  of  the  interference  with  the  ingestion 
of  food  or  from  disease  of  the  respiratory  organs  because 
of  the  unlimited  entrance  of  air. 


172  ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE 

For  these  reasons  the  treatment  is  of  great  interest  to 
surgeons  and  dentists.  That  of  hare-bp  consists  in  insti- 
tuting as  soon  as  possible  a  surgical  operation  with  the 
object  of  securing  union  of  the  edges  of  the  lip  by  scraping 
them  and  then  suturing  them  together ;  this  is  called 
cheilopkisty.  The  principle  of  the  treatment  of  the  deft 
jxilate  is  similar  to  the  former  ;  in  this  case,  too,  the  edges 
are  fastened  and  sutured.  This  operation  on  the  hard 
palate  is  termed  uranoplasty.  As  there  is  always  insuf- 
ficient mucous  and  periosteal  membrane,  it  does  not 
suffice  simply  to  unite  the  two  edges  of  the  wound,  but 
in  addition  two  lateral  incisions  should  be  made  parallel 
to  the  cleft,  one  on  each  side  in  order  that  the  tissues  may 
be  stretched.  The  operation  on  the  soft  palate,  called 
staphylorrhaphy,  consists  in  uniting  the  velum  palati  with 
the  uvula. 


Fig.  68.— Palatine  obturator  of  Suersen  :  a,  dental  plate  ;  h,  fixed  connecting 
process  ;  c,  hard  rubber  head  piece. 

It  is,  however,  often  impossible,  when  the  defect  is  too 
extensive,  to  secure  union  by  means  of  the  above  oper- 
ations. In  such  cases  it  is  necessary  to  employ  an 
obturator;  that  is,  an  apparatus  which  will  close  the 
defect.  If  only  a  coloboma  or  a  cleft  of  the  hard  jxdate 
be  present,  it  is  quite  easy  to  close  the  defect.  This  is 
done  simply  by  forming  a  palatine  plate  from  India- 
rubber  or  metal,  and  attaching  it  to  the  teeth  by  gold 
clasps.  In  the  case  of  defects  of  the  soft  palate  the  con- 
struction of  an  apparatus  is  not  so  simple,  because  of  the 
functions  of  this  part — talking  and  swallowing.  A  simple 
and  useful  apparatus  for  this  purpose  has  been  constructed. 


ACQUIRED  AND  CONGENITAL  DEFECTS  OF  FACE.  173 

by  Suersen.  It  is  based  on  the  physiologic  principle  that, 
during  speaking  and  swallowing,  the  communication 
between  the  oral  and  nasal  cavity  must  constantly  close 
and  open. 

In  the  healthy  person  this  closure  is  obtained,  on  the  one 
side,  by  elevation  of  the  lavator  palati  muscle  and  with  it 
the  velum.  Simultaneously,  on  the  other  side,  the  sujjerior 
constrictor  muscle  of  the  pharynx  contracts,  and  thus 
forces  the  posterior  pharyngeal  wall  forward.  In  this 
manner  the  velum  palati  and  pharyngeal  wall  are 
brought  together,  and  form  an  air-tight  closure  which 
may  open  at  any  time  or  to  any  degree.  Such  require- 
ments are  fulfilled  by  the  apparatus  of  Suersen,  which 
replaces  the  velum  palati  with  a  hard  mass  (hard  rubber), 
shaped  like  that  structure.  That  portion  of  the  velum 
which  may  be  present  glides  into  the  lateral  grooves  of 
the  apparatus. 


Fig.  i">9.— Palatine  obturator  of  Schiltsky,  in  a  somewhat  altered  form :    a, 
dental  plate  ;  b,  lock;  c,  spiral  spring;  d,  soft  rubber  bulb. 

When  the  pharyngeal  wall  bulges  forward  it  presses 
against  the  posterior  wall  of  the  obturator,  and  thus 
divides  the  nasopharyngeal  wall  into  an  upper  pharyngo- 
na.sal  cavity  and  a  lower  pharyngo-oral  cavity.  Thus 
the  required  closure  is  obtained.  The  obturator  of 
Suersen  can  only  be  employed  when  the  velum  ])alati  is 
absent ;  if  it  still  exist  and  still  show  fairly  good  union, 
or  when  a  staphylorrhaphy  has  been  previously  per- 
formed with  some  success,  we  must  resort  to  other 
remedies. 


174  ANOMALIES  OF  THE  TEETH  AND   TEE  JAWS. 

Schiltsky  has  solved  the  problem  of  applying  an  obtu- 
rator in  those  cases  in  which  the  velum  palati  still  par- 
tially exists.  According  to  his  method,  the  closing  of  the 
nasopharyngeal  space  is  obtained  by  means  of  an  elastic 
balloon  which  responds  to  all  the  changes  in  form  that 
occur  in  speaking  and  swallowing.  By  means  of  a  spiral 
spring  the  balloon  is  connected  with  a  plate  covering  the 
hard  palate  ;  this  arrangement  permits  all  movements  of 
the  soft  palate  to  be  shared  by  the  balloon.  Although 
more  easily  destroyed  than  hard  rubber  it  is  better  to 
construct  the  bladder  of  soft  rubber,  as  hard  rubber  tends 
to  cause  pressure  (Fig.  69).  The  soft  rubber  "bulb" 
should  be  made  as  light  as  possible,  in  order  thi!t  its 
weight  will  not  draw  the  spring  downward,  a  condition 
which  would  prevent  its  responding  to  the  movements  of 
the  soft  palate.  This  is  best  accomplished  by  vulcanizing 
a  nucleus  of  cork  into  its  center. 


ANOMALIES  OF  THE  TEETH  AND  THE  JAWS, 

With  reference  to  the  causation  of  anomalies  of  the 
teeth  and  jaws,  Virchow  observes  that  on  the  one  side  the 
normal  pressure  of  the  tongue,  and  on  the  other  side,  that 
of  the  lij^s  and  cheeks  is  of  greatest  importance  for  the 
proper  position  of  the  teeth.  In  addition  to  these  two 
influeuces,  we  have  that  of  the  normal  act  of  cheicinc/, 
which  may  also  affect  the  position  of  the  teeth.  The 
same  writer  claims  that  prognathism  of  the  upper  jaw 
occurs  in  cretins  because  the  tongue  becomes  enormously 
enlarged  and  forces  the  teeth  forward.  Prognathism  of 
the  loicer  jaic  is  especially  likely  to  develop  in  persons 
possessing  a  cleft  palate,  because  the  stretched  upper  lip 
presses  on  the  upper  incisors,  while  the  tongue  presses 
upon  the  lower  teeth.  Furthermore  adenoid  growths  of 
the  pharynx  require  the  mouth  to  be  kept  open,  and  as  a 
result  the  teeth  do  not  bite  upon  each  other,  and  the  con- 
sequent influence  upon  the  buccal  pressure  may  lead  to  a 
narrow  superior  maxilla. 


ANOMALIES  OF  THE  TEETH  AND  THE  JAWS.   175 

Undoabteclly,  the  first  cause  of  such  anomalies  in 
healtiiy  persons  is  insujiciency  of  space,  due  to  the  fact 
that  children  of  civilized  races  inherit  small  jaws.  The 
teeth  then  press  each  oiher  out  of  position.  This  argu- 
ment of  Sternfeld  is  contradicted  by  Warnekros,  who 
assumes  that  the  inheritance  of  a  small  jaw  must  neces- 
sarily mean  the  inheritance  of  small  teeth,  because  of  the 
degeneration  following  inactivity.  However,  we  may 
accept  the  theory  of  the  insufficiency  of  space,  for  Riiti- 
meyer  has  determined  that  the  teeth  very  frequently 
show  evolutionary  vestiges,  indicating  that  teeth  undergo 
alteration  less  rapidly  than  the  surrounding  structures. 
Accordingly  we  have  inherited  the  large  teeth  of  our  fore- 
fathers, and  the  small  jaws  of  our  parents.  That  this  is 
true  has  also  been  shown  by  AValkhofT,  who  explains  it  by 
the  character  of  tooth  development.  If  the  outer  plate  of 
the  human  jaw  be  chiselled  away  at  the  time  of  the  sub- 
stitution of  the  deciduous  by  the  permanent  teeth,  it  will 
be  observed  that  the  secondary  teeth  germs  are  extremely 
irregular  in  their  arrangement  between  the  roots  of 
the  first  teeth.  This  irregularity,  however,  is  found  only 
in  civilized  people  ;  barbarians  retain  a  perfect  regularity 
in  the  arrangement  of  their  teeth.  In  consequence  of  the 
irregular  position  of  the  secondary  tooth  germ,  the  resorp- 
tion organ  is  forced  out  into  a  false  jjosition,  or  not  at  all 
against  the  deciduous  tooth. 

The  premature  loss  of  the  first  teeth  has  an  extremely 
disadvantageous  influence  upon  the  permanent  teeth.  This 
is  particularly  true  of  the  second  deciduous  molars  which 
should  be  retained  as  long  as  possible.  If  these  temporary 
molars  are  lost  prematurely  either  through  extraction  or 
caries,  the  first  permanent  molar  rises  immediately  into 
the  alveolus  and  deprives  the  bicuspid  teeth  of  their  proper 
space,  which  therefore  must  seek  a  false  position  when  they 
erupt  later.  According  to  WalkhofF,  there  results  a 
remarkable  tendency  of  the  teeth  within  the  curvature  of 
the  dental  arch  to  close  tightly  the  tooth  row. 

If  permanent  teeth  are  tost,  the  remaining  teeth  become 
easily  displaced.     This  is  especially  the  case  when   the 


176  ANOMALIES  OF  THE  TEETH  AND   THE  JAWS. 

articulation  of  the  molars  is  destroyed,  for  then  the  anterior 
teeth  become  displaced  forward.  If  an  antagonist  be 
absent,  the  opposite  tooth  grows  in  length  in  its  endeavor 
to  reach  the  other  tooth  within  the  space,  until  it  becomes 
loose  and  falls  out. 

Frequently  too  many  germs  are  constricted  from  the 
tooth  band  which  occasionally  erupt,  and  nearly  always 
outside  of  the  normal  tooth  row,  because  they  can  find  no 
place  within  it.  More  rarely  an  insufficient  number  of  teeth 
are  formed.  This  occurs  occasionally  in  cretins  and  in 
imbeciles,  and  also  when  normally  developed  teeth  become 
eliminated  during  the  course  of  evolution.  It  is  well 
known,  for  instance,  that  the  third  molar  tooth  tends  to 
disappear  in  civilized  people,  while  the  same  tooth  in  bar- 
barians still  possesses  its  full  size.  The  upper  lateral 
incisors  also  tend  to  undergo  degeneration,  and  not  infre- 
quently we  find  people  without  this  tooth  (Fig.  62  a). 

Amoedo  has  called  attention  to  the  interesting  fact  that 
a  certain  connection  exists  between  the  development  of 
hair  and  that  of  teeth  ;  namely,  that  hairy  people  have  too 
few  and  insufficiently  developed  teeth. 

Aberration  of  the  tooth  band  may  lead  to  heterotopy, 
that  is,  one  tooth  may  erupt  in  the  space  belonging  to 
another. 

Constitational  diseases,  for  example,  rhachitis,  scrofula, 
and  inherited  syphilis,  may  cause  deformities  of  the  teeth 
and  the  jaws,  and  thus  lead  to  irregularity  in  the  position 
of  the  teeth,  as  well  as  absence  of  individual  teeth. 

Finally,  attention  must  be  called  to  the  effect  of  trauma- 
tism upon  anomalies  in  the  position  of  the  teeth.  A  frac- 
ture, in  as  much  as  it  is  associated  with  dislocation  of  a 
portion  of  the  jaw  that  contains  teeth,  may  lead  to  disloca- 
tion of  one  or  more  teeth.  To  the  class  of  traumatism 
belong  the  conditions  following  the  habit  of  sucJdng  the 
thumb  and  other  objects,  both  of  which  may  cause  in  chil- 
dren disharmony  of  the  dental  arch. 

The  disturbances  influenced  by  irregularity  of  the  teeth 
are  of  a  cosmetic  nature  ;  that  is,  the  appearence  suffers 
to  a  greater  or  less  extent.     Mastication  is  also  interfered 


ANOMALIES  OF  FORM  IN  INDIVIDUAL  TEETH.     177 

with  when  the  occluding  surfaces  of  the  opposing  teeth  do 
not  meet.  Furthermore  irregularly  set  teeth  may  injure 
the  mucous  membrane  of  the  lips  and  cheeks  as  well  as 
the  tongue.  They  may  even  occasionally  interfere  with 
speech,  especially  when  the  tongue  strikes  on  dislocated 
teeth  ;  indeed  stuttering  has  been  observed  to  follow  such 
an  anomaly. 

Irregularly  set  teeth  are  more  susceptible  to  caries  than 
the  normal  teeth,  because  it  is  more  difficult  to  keep  them 
clean.  This  is  especially  the  case  when  the  tooth  stands 
within  or  without  the  dental  arch.  In  jrrognathism  and 
in  orthognathism,  in  which  the  incisors  of  the  upper  and 
lower  jaws  articulate  improperly,  the  teeth  are  ground 
down  prematurely.  This  also  frequently  occurs  when  the 
molars  fail  to  articulate  properly.  The  anomalies  may 
present  the  following  varieties. 

ANOMALIES  OF  FORM  IN  INDIVIDUAL  TEETH. 

The  form  and  the  size  of  the  crown  as  well  as  of  the 
roots  of  the  tooth  may  show  considerable  variations.  The 
roots  are  especially  likely  to  be  the  seat  of  abnormal  con- 
ditions. 


Fig.  70.  — Upper  lateral  Fig.  71.— Upper  cuspid  Fig.  72.— Lower  bicuspid 
Incisor  tooth  with  two  tooth  with  two  roots.  tooth  with  a  hook-shaped 
roots.  curvature  oftlie  root. 

Incisor  and  cuspid  teeth  frequently  have  two  roots,  (Figs. 
70  and  71).  Their  roots  also  occasionally  show  great 
irregularity.  This  is  true  also  of  the  bicuspid  teeth.  In 
Figs.  72  and  73  are  shown  bicuspid  teeth  with  crooked 
roots.  A  peculiarly  constructed  iirst  upper  bicuspid  tooth, 
12 


178     ANOMALIES  OF  FORM  IN  INDIVIDUAL   TEETH. 

composed  apparently  of  two  individual  teeth,  is  shown  in 
Fig.  74. 

The  cases  are  rare  in  which  the  first  upper  bicuspid 
which  usually  possesses  but  two  roots  have  three  roots. 
Such  a  tooth  is  shown  in  Fig.  75. 


Fig.  73.— Lower  pre- 
molar with  peculiarly 
curved  root. 


Fig.  74.— Fir.st  upper  bicuspid, 
which  is  curved  to  such  an  ex- 
tent on  its  longitudinal  axis  as 
to  give  the  impression  that  it 
consists  of  two  teeth  grown  to- 
gether. 


Fig.  75.— First  upper 
bicuspid  with  three 
roots. 


The  roots  of  the  molar  teeth  are  even  more  frequently 
abnormal  than  those  of  the  front  teeth.  A  high  grade 
divergence  (Fig.  76),  as  well  as  an  equally  high  grade 
convergence  (Fig.  77),  are  not  so  very  infrequently 
observed.      Both    conditions    increase    the    difficulty  of 


Fig.  76.— Upper  molar  Fig.  77.— Lower  molar  Fig.  78. — Lower  incisor 
tooth  with  decidedly  with  decidedly  con verg-  tooth  with  five  tortuous 
diverging  roots.  ing  roots.  roots.      (All  the    roots  are 

not  shown  in  this  illustra- 
tion.) 

sounding  the  roots  as  well  as  extracting  teeth.  Of  the 
many  abnormalities  of  the  third  molar  or  wisdom  teeth 
that  are  met  with  only  one  is  presented  (Fig.  78).  In 
this  case  a  lower  wisdom  tooth  possesses  five  bent  roots. 


ANOMALIES  IN  POSITION  OF  TEETH.  179 

ANOMALffiS  IN  POSITION  OF  INDIVIDUAL  TEETH. 

Although  individual  teeth  may  occasionally  stand  in 
their  normal  position  in  the  tooth  row,  they  may  be 
twisted  on  their  long  axis  (Fig.  79).  They  may  vary, 
however,  in  all  possible  directions  from  their  normal 
position.  This  torsion  occurs  more  frequently  in  the 
incisor  teeth  and  indeed  more  often  in  the  upper  than  in 
the  lower.  However  all  the  remaining  teeth,  but  most 
rarely  the  molars,  are  subject  to  this  anomaly. 


Fig.  79.— Torsion  of  a  left  upper  incisor  tooth. 

Furthermore,  a  tooth  may  stand  to  the  outside  or  to 
the  inmic  of  the  dent(d  arch.  The  first  anomaly  is  very 
often  observed  in  the  upper  cuspids,  which,  at  the  time  of 
eruption,  find  the  space  a.ssigned  to  them  already  occupied 
and  therefore  are  forced  to  erupt  to  the  outside.  The  lower 
incisor  teeth  may  also  erupt  in  a  lingual  direction  and  the 
upper  incisors  in  a  ]>alatinal  direction  from  the  dental 
arch  (see  Figs.  SO  and  81).  The  bicuspids  are  much  more 
rarely  located  outside  of  the  dental  arch,  and  when  they 


180 


ANOMALIES  IN  POSITION  OF  TEETH. 


are,  it  may  be  nearly  always  assumed  that  the  corresponding 
deciduous  tooth  was  lost  too  soon,  allowing  the  space  to 
close  up  before  the  permanent  teeth  made  their  appearance. 


Fig.  80. — Lateral  upper  incisor  toolh  turned  in  a  palatinal  direction  from 
the  dental  arch. 


Fig.  81.— Three  incisor  teeth  of  the  upper  Jaw  which  erupted  to  the  palatinal 
side  of  the  dental  arch. 

The  condition  in  which  two  teeth  exchange  their  posi- 
tions, or  in  which  one  tooth  is  located,  in  the  space  be- 
longing to  another,  is  known  as  heterotopia  or  in  a  popular 


ANOMALIES  IN  POSITION  OF  TEETH. 


181 


sense,  transposition.     The  bicuspids  are  the  most  prone  to 
exchange  their  positions  Avith  the  incisor  teeth.      Magitot 


^■' 


Fig.  S2.— Supernumerary  tdiitli  between  the  Hrst  and  second  right  lower  molar. 


speaks  of  a  keterotoiyia  jicir  c/en^^e,  when  teeth  outside  of 
the  tooth-roAv  erupt  into  the  hard  palate,  the  antrum  of 
Hiiriiinore,  and  even  into  the  orbit. 


182  SUPEBNUMEBABY  TEETH. 

PLATE  i6. 

Prognathism.  The  upper  jaw  together  with  the  base  of  the  nose  is 
extended  forward  at  an  extreme  degree.  The  lower  jaw  is  normal. 
From  a  child  16  years  of  age. 

PLATE   17. 

Prognathism.  The  lower  jaw  protrudes  to  such  an  extent  that  its 
teeth,  when  the  mouth  is  closed,  lie  in  front  of  those  of  the  upper  jaw. 
The  superior  maxilla  is  normal.     From  a  woman  50  years  of  age. 

SUPERNUMERARY  TEETH.  AN  INSUFFICIENT 
NUMBER  OF  TEETH. 

Supernumerary  teeth  show  various  formations.  They 
either  simulate  normal  teeth  or  represent  simple  cuspid 
teeth.  They  owe  their  origin  to  an  overproduction  of 
enamel  germs  which  have  sprouted  and  attached  them- 
selves to  the  connecting  band  between  the  primary  tooth 
germ  and  the  oral  epithelium,  or  to  the  secondary  enamel 
germ  itself. 

Busch  considev^  gQwwme peg-shaped  teeth  as  independent 
forms,  which  have  been  separated  from  the  primary  tooth 
germ  by  mechanical  influences.  Contrary  to  the  obser- 
vation of  other  investigators,  he  does  not  look  upon  the 
formation  of  these  teeth  as  atavistic  phenomena,  a  view 
which  one  would  be  justified  in  believing  when  the  original 
haplodont,  multi-toothed  type  of  the  mammals  is  taken 
into  consideration. 


Fig.  83.— The  lateral  left  incisor  tooth  failed  to  reach  development  (reduction). 

Supernumerary  teeth  occur  more  frequently  in  the  region 
of  the  incisors  than  in  that  of  the  molar  teeth ;  super- 
numerary molar  teeth  are  however  occasionally  seen.  An 
example  of  this  type  of  tooth  is  pictured  in  Fig.  82. 


'\V^ 


Tab.16. 


Tab.  17. 


SUPERNUMERARY  TEETH. 


183 


Fig.  iA.—  Vpper  illustration.  The  normal  width  of  the  palate.    Loiver  illuMra- 
tion.  A  contracted  palate  which  is  retracted  iu  the  region  of  the  bicuspid  teeth. 


184    ANOMALIES  OF  THE  WHOLE  TOOTH  BOW. 
PLATE  i8. 

Mordex  apertus.  Althougli  the  molar  teeth  touch  each  other  in 
this  case,  yet  the  patient  is  unahle  to  bring  the  front  teeth  of  the  two 
jaws  together. 

An  insuffieient  nwnber  of  teeth  is  of  less  importance  to  the 
practitioner  than  an  abnormally  large  number.  This 
condition  may  be  due  to  a  retrogressive  process  of  the 
human  dental  apparatus.  As  examples  of  this  anomaly, 
to  which  reference  has  already  been  made,  we  have  the 
wisdom  and  the  upper  lateral  incisor  teeth  (see  Fig.  83), 
which,  according  to  the  observations  of  most  authorities, 
have  undergone  retrogressive  changes.  In  explaining  the 
failure  of  some  teeth  to  appear  in  the  tooth  row,  we  must 
take  into  account  the  retention  of  tooth  germs,  or  of  fully 
developed  teeth. 

ANOMALIES    OF    THE    WHOLE    TOOTH    ROW    WITH 
AND  WITHOUT    CHANGES   IN  THE   JAW. 

In  people  of  the  civilized  races,  when  the  two  sets  of 
teeth  occupy  normal  positions,  the  lingual  surface  of  the 
upper  incisors  in  closing  the  mouth  should  glide  past 
the  labial  surface  of  the  lower  incisors.  When  the  two 
sets  of  teeth  bear  this  normal  relationship  to  each  other, 
the  condition  is  called  orthognathism.  Should  the  teeth 
not  meet  in  this  manner  the  cutting  edges_  of  the  incisors 
instead  resting  upon  those  of  their  opposite  fellows,  the 
result  is  a  rapid  wearing  away  of  the  incisors  of  both 
jaws  ;  they  may  eventually  be  worn  oflP  down  to  the  edge 
of  the  gums.  In  the  ancient  Egyptians  and  Celts,  this 
condition  is  believed  to  have  been  physiologic. 

Jn  prognathism  of  the  upper  jaw  (Plate  16),  when  the 
mouth  is  closed,  the  upper  teeth  no  longer  reach  the  lower, 
but  stand  above  and  in  front  of  the  lower  set  of  teeth. 
This  pathologic  prognathism  is  not  to  be  mistaken  for  the 
physiologic  form  as  seen  in  negroes,  in  which  both  the 
upper  and  lower  jaws  protrude. 


'/'.l  .' 


Xi 


lab.  IS. 


■4% 


ANOMALIES  OF  THE   WHOLE  TOOTH  BOW.     185 

Pathologic  prognatliism  shows  many  variations  ;  it  may 
consist  simply  iu  a  moderate  extension  for\vard  of  the 
upper  teeth  which  are  separated  from  the  lower  teeth  by 
only  a  few  millimeters  ;  or  the  separation  may  equal  a 
centimeter,  in  which  case,  of  course,  the  superior  maxilla 
has  developed  to  an  unusual  size.  In  many  cases  prog- 
nathism of  the  upper  jaw  is  simulated  by  failure  of  the 
lower  jaw  to  develop  to  its  normal  size,  while  the  superior 
maxilla  is  fully  developed.  If,  on  the  other  hand,  the 
lower  jaw  protrudes,  we  have  the  condition  known  as 
pror/iiathisiii  of  the  inferior  maxilla  (Plate  17).  According 
to  Virchow,  the  lower  jaw  of  the  inhabitants  of  Fries- 
land  protrudes  normally  so  far  beyond  the  upper  jaw,  that 
the  lingual  surface  of  the  lower  incisors  points  to  the 
labial  surface  of  the  upper  incisor  teeth.  The  pathologic 
form  of  prognathism  of  the  lower  jaw  is  not  always  due 
to  excessive  growth  of  the  inferior  maxilla  (analagous  to 
prognathism  of  the  upper  jaw),  for  on  the  contrary  it  may 
be  normal  in  development,  the  superior  maxilla  having 
failed  to  reach  its  normal  size. 

3fordex  apertus  carabelli  (Plate  18),  or  "malocclusion," 
is  a  rare  condition  in  which  the  two  rows  of  teeth  do  not 
meet  in  the  neigliborhood  of  the  incisors.  It  occurs 
chiefly  in  children  who  suffer  from  hypertrophied  tonsils 
or  from  adenoid  growths  of  the  nasopharynx,  on  account 
of  Avhich  the  mouth  is  continually  kept  open.  As  a 
result  the  alveohir  portion  of  the  jaws  in  the  region  of 
the  molars  grows  abnormally  large. 

The  contracted  jaw  (Fig.  84,  lower  illustration),  which 
undergoes  a  saddle-like  contraction  in  the  neighborhood 
of  the  bicuspid  teeth,  may  also  occasionally  cause  progna- 
thism and  mordex  apertus.  This  condition  is  alwavs  asso- 
ciated with  a  liigh  ])alate,  and  is  really  an  anomaly  of  the 
jaw  ill  which  the  teetli  do  not  assume  their  altered  positions 
until  the  second  dentition.  Down  found  the  contracted 
jaw  with  a  higli  palate  chiefly  in  idiots. 

The  so-called  V-shaped  jaw  (Fig.  85)  must  not  be  mis- 
taken for  a  contracted  jaw.  The  former  does  not  possess 
a  dental  arch,  but  instead  the  teeth  form  a  straight  line 


186     ANOMALIES  OF  THE   WHOLE  TOOTH  BOW. 

on  each  side,  meeting  at  the  incisor  teeth  to  form  an  acute 
angle. 

This  V-shaped  jaw,  which  is  considerably  below  normal 
in  size,  does  not  occar  in  idiots  but  on  the  contrary  is  very 
frequently  seen  in  intelligent  and  well-developed  individ- 
uals. It  represents  probably  a  retrogressive  process  in 
which  the  jaw  becomes  reduced  in  size  at  the  expense  of 
the  cranial  portion.  A  high  palate  and  prognathism  of 
the  upper  jaw  are  also  associated  with  the  V-shaped  jaw. 

The  treatment  varies  with  the  requirements  of  each 
individual  case  and  should  not  be  instituted  until  important 
indications  arise.  The  treatment  of  anomalies  in  position 
of  individual  teeth  is  purely  operative.  The  cause  of 
such  anomalies  can  usually  be  traced  to  a  lack  of  space, 
and,  therefore,  in  such  cases  it  is  necessary  above  all  things 
to  secure  more  room.     This  is  done  by  spreading  the  arch 


Fig.  85.— V-shaped  palate  in  a  child  15  years  of  age. 

and  thus  securing  the  desired  space  ;  or  by  the  extraction 
of  a  neighboring  tooth,  especially  when  it  is  less  developed 
than  the  improperly  placed  tooth.  The  latter  then  moves 
of  its  own  accord  into  its  proper  location.  If,  because  it 
is  sound  and  healthy,  there  should  be  any  hesitancy  to 
sacrifice  it,  other  teeth  may  be  extracted,  as  for  example, 
the  bicuspids  and  molars.  The  dental  arch  is  then  easily 
forced  to  assume  its  normal  relations  by  applying  a  proper 


ANOMALIES  OF  THE   WHOLE  TOOTH  ROW.     187 

regulatiou  apparatus.  As  we  have  already  suggested,  the 
most  satisfactory  results  are  obtained  by  expanding  the 
whole  jaw  in  order  to  obtain  the  requisite  amount  of  room. 


Fig.  86.— Coflin  i)]ate  for  expansion  of  a  narrow  palate. 


Fig.  87.— Regulating apparatu.s  for  twisted  teeth  when  suffiqjent  space  exists. 
The  motive-power  on  the  left  side  is  obtained  by  means  of  gold  wire  and  on 
the  right  by  caoutchouc. 

This  process,  however,  requires  much  time  and  is  incon- 
venient. Coffin  has  invented  an  appliance  (Fig.  SQ)  for 
expansion  of  the  jaw,  which  consists  of  a  divided  plate, 
each  half  of  which  is  pressed  apart  by  means  of  a  spring. 


18S     ANOMALIES  OF  THE  WHOLE  TOOTH  BOW. 

Both  jaws,  however,  must  be  expanded,  for  otherwise  artic- 
ulation will  be  interfered  with. 

For  the  correction  of  torsion  (with  or  without  sufficient 
space)  an  apparatus  is  employed  constructed  according  to 
the  principle  of  that  illustrated  in  Fig.  87.  It  consists 
simply  of  a  fixed  portion  (palate  plate  or  gold  crown),  and 
a  movable  portion  which  serves  as  the  motive-power  (wire 
spring,  caoutchouc,  etc.).  The  motive-power  will  in  a 
short  time  draw  the  tooth  into  its  proper  position.  But 
if  a  dental  arch  lacks  sufficient  space,  an  apparatus  like 
that  illustrated  in  Fig.  88  gives  better  satisfaction.  Its 
action  consists  in  moving  several  teeth  toward  a  space 
that  has  been  secured  by  extraction  of  a  tooth  and  thus 
obtaining  sufficient  room  for  a  tooth  that  has  been  forced 
to  grow  in  an  abnormal  position. 


Fig.  88.— a  regulation  apparatus  which  is  intended  to  draw  the  left  upper 
tooth  row  backward  for  a  distance  equal  to  the  width  of  the  first  molar  tooth, 
which  has  been  extracted  in  order  to  obtain  sufficient  space  for  a  twisted  tooth. 

Supernumerary  teeth  should  be  corrected  only  when  they 
actually  cause  harm.  As  they  are  in  nearly  all  cases 
abnormally  situated  and  formed,  their  removal  can  hardly 
be  considered  disadvantageous. 

The  treatment  of  an  insiifficient  number  of  teeth  is  not 


ANOMALIES  OF  THE   WHOLE  TOOTH  BOW,    189 

altogether  so  unsatisfactory  as  is  commonly  supposed.  An 
attempt  should  ahvays  be  made  by  means  of  expansion  to 
facilitate  the  eventual  eruption  of  a  retained  tooth. 

Such  treatment  is  also  very  satisfactory  in  those  cases 
in  which,  in  spite  of  sufficient  room,  a  tooth  fails  to  erupt. 
When  it  has  been  determined  by  means  of  a  radiograph 
that  no  tooth-germ  exists,  the  space  should  be  closed  by 
employing  an  apparatus  that  will  draw  the  back  teeth  for- 
ward until  this  space  is  obliterated.  This  procedure, 
however,  can  only  be  carried  out  satisfactorily  in  the  front 
teeth,  or  the  space  may  be  filled  by  an  artificial  tooth. 

As  regards  anomalies  of  a  whole  tooth-row,  orthopedic 
surgery  should  be  resorted  to  iu  the  treatment  of  path- 
ologic prognathism  of  the  upper  jaw,  which  should  be  com- 
bined with  extraction  of  molar  teeth.  The  latter  is 
unnecessary  if  the  teeth  are  far  apart.  If  the  jaw  be 
sufficiently  wide,  the  front  teeth  are  simply  drawn  back- 
ward with  a  symmetrically  curved  metallic  splint.  For 
the  purpose  of  fixing  the  traction-apparatus  a  plate  is  pre- 
ferred, although  gold  crowns  cemented  to  the  molars  are 
also  of  advantage.  A  high  grade  opisthognathism  is  cor- 
rected by  applying  incline  planes  which  force  the  lower 
jaw  forward ;  this  finally  causes  the  formation  of  a  new 
maxillary  joint,  slightly  anterior  to  that  of  the  original 
joint.  This  form  of  correction  is  more  satisfactory  than 
forcing  the  lower  front  teeth  forward. 

In  case  of  a  contracted  and  V-shaped  jaw  expansion  is 
as  important  as  retraction,  and  one  may  therefore  employ 
with  advantage  a  retraction  apparatus,  together  with  a 
Co/fin  plate.  This  double  action  through  one  machine 
may  be  obtained  by  making  the  retraction  splint  from  a 
gold  wire  spring.  If  this  spring  splint  be  fastened  to  a  molar 
tooth  that  carries  on  its  lingual  side  a  strong  splint 
attached  to  the  remaining  teeth,  the  retraction  will  be 
simultaneous  with  expansion. 

Profpuithism  of  the  lower  jaw  is  treated  similarly  to 
that  of  tlie  upper  one.  It  is  advisable  not  to  undertake 
to  shorten  the  lower  jaw  until  space  has  been  procured  by 
the  removal  of  certain  teeth. 


190  DENTAL  DEPOSITS. 

After  the  position  of  a  tooth  has  been  corrected  it  must 
in  each  case  be  Jixecl  for  a  considerable  length  of  time, 
otherwise  the  former  condition  will  return  soon  after  the 
apparatus  has  been  removed.  The  untoward  effects  which 
may  develop  after  the  use  of  a  regulation  apparatus  are 
due  to  the  injuries  caused  by  clamps  and  splints.  The 
injuries  do  not  result  from  the  sharp  borders  of  the  gold 
wire  bringing  about  defects  in  the  enamel  as  described 
by  Sternfeld.  It  is  more  likely  that  under  those  circum- 
stances destructive  processes  tend  to  develop  which  attack 
the  enamel.  Therefore,  the  smaller  the  size  of  the  por- 
tions of  an  apparatus  which  comes  in  contact  with  a  tooth, 
the  less  the  injury  which  may  follow  its  use. 

DENTAL  DEPOSITS. 

Calcium  salts,  especially  the  phosphate  and  carbonate 
of  lime,  are  precipitated  from  the  saliva.  If  they  form 
hard  crusts,  the  deposits  are  commonly  called  tartar. 
This  is  found  in  large  amounts  in  the  region  of  the 
excretory  ducts  of  the  salivary  glands,  and  therefore,  on 
the  buccal  side  of  the  upper  molars  and  on  the  lingual 
surface  of  the  lower  incisor  teeth.  Tartar  may,  however, 
be  deposited  on  all  exposed  surfaces  (see 
Fig.  89).  Only  small  amounts  of  tartar 
occur  in  the  mouths  of  cleanly  persons, 
while  in  persons  who  use  a  brush  insuf- 
ficiently a  large  number  of  teeth  may 
show  a  thick  layer  of  this  accumulation. 
This  deposit  does  not,  however,  consist 
mo/ar  with  ^thTck  entirely  of  lime,  but  may  include  various 
crusts  of  tartar  at     elements,  sucli  as  remnants  of  food,  epi- 

tne  tooth  neck.  ,t     t    i         n  t  t       ,      •  ■ 

thehal  cells,  and  numerous  bacteria. 
On  account  of  the  organic  constituents,  especially 
when  soft  in  consistency,  putrefactive  and  fermenta- 
tive changes  take  place  which  cause  a  nauseating 
odor.  The  gums  and  the  rest  of  the  oral  mucous 
membrane  become  considerably  irritated,  which  explains 
why  digestion  and  the  general  health   suffer.     The. soft 


I 

I 


DENTAL  DEPOSITS.  191 

white  deposits  are  distinguished  from  true  tartar  because 
they  include  a  greater  amount  of  food  remnants  under- 
going degeneration,  as  well  as  mucous  and  epithelial 
cells.  Green,  brown,  and  black  deposits,  as  are  shown 
in  Plate  21,  Figs.  4,  5,  and  6,  occur  chiefly  on  the 
labial  surface  of  the  upper  front  teeth,  and  occasionally 
on  all  other  surfaces  of  the  teeth.  These  are  usually  not 
real  deposits,  for  the  substance  penetrates,  as  has  been 
demonstrated  by  Miller,  into  the  substance  of  the  outer 
layer  of  the  enamel,  but  without  affecting  the  enamel  itself. 

The  nature  of  these  deposits  is  not  as  yet  thoroughly 
understood,  excepting  of  course  those  cases  in  which  the 
discoloration  is  due  to  medicaments  (mercury,  iron,  etc.). 
It  is  also  known  that  the  smoking  of  tobacco  causes  a 
rusty-colored  deposit  to  develop  on  the  teeth. 

Like  the  etiology,  we  are  still  in  the  dark  as  to  the 
influence  of  colored  deposits  upon  the  tooth  substances. 
Inasmuch  as  tartar  displaces  the  gum  with  subsequent 
loosening  of  the  teeth,  it  is  necessary  to  remove  it  period- 
ically. This  is  best  done  with  especially  constructed 
instruments.  In  order  to  avoid  injuring  the  gums  as 
well  as  the  surface  of  the  teeth,  tlie  tartar  situated  at  the 
neck  of  the  tooth  should  be  removed  with  great  care. 
This  may  be  brought  about  by  carefully  pushing  the  gum 
far  enough  back  with  a  suitable  instrument  to  permit  the 
prominent  edge  of  the  tartar  to  be  grasped  and  loosened. 

Colored  deposits,  especially  the  green,  are  nearly  always 
difficult  to  remove,  at  least,  by  mechanical  means.  Tlie 
best  method  consists  in  the  use  of  a  circular  brush  and 
pulverized  emery.  Assistance  may  be  secured  by  the  use 
of  certain  chemicals.  Some  obtain  excellent  results  with 
the  tincture  of  iodin,  others  with  a  10  per  cent,  solution 
of  liydrogen  peroxid.  The  technic  is  very  simple  and 
need  not  here  be  described. 


192     DEFECTS  OF  THE  HARD   TOOTH  SUBSTANCES. 

CONGENITAL  DEFECTS  OF  THE  HARD 
TOOTH  SUBSTANCES. 

Congenital  defects  of  the  enamel  were  formerly  called 
erosions.  This  term  gives  the  impression  that  these 
fossae  and  other  changes  may  follow  the  action  of  any 
irritant,  such  as  acids,  upon  the  surface  of  the  tooth.  As 
Berten  shows,  this  does  not  take  place  but  instead,  a 
defective  development  of  each  individual  tooth  occurs. 
The  condition  is  therefore  a  hypoplasia,  a  term  which 
Zsigmondy  applies  to  this  phenomenon  because  of  anal- 
agous  patho-anatomic  processes.  The  term  erosion  is 
reserved  for  certain  acquired  defects.  The  etiology  of 
hypoplasia  is  already  expressed  in  the  name.  It  is  an 
arrest  in  growth  during  the  developmental  period. 
Syphilis,  rhachitis,  and  scrofula  must  be  looked  upon  as 
the  chief  factors  of  this  disturbance.  These  hypoplasise 
present  the  following  forms,  which  however  are  not 
sharply  defined  but  tend  to  pass  from  one  into  another: 

1.  Undulations. 

2.  Lacunae. 

3.  Grooves. 

4.  Partial  or  complete  absence  of  the  enamel. 

5.  Crescentic  defects. 

6.  Odontoporosis. 

Undulations.  A  dentist  who  is  a  careful  observer 
will  frequently  see  cases  in  his  practice  in  which  the 
teeth  present  an  undulatory  surface.  Inasmuch  as  the 
enamel  is  otherwise  perfectly  normal,  and  possesses  a  shiny 
smooth  surface,  this  condition  often  escapes  detection.  In 
such  cases  an  enamel  hyperplasia  may  be  suspected. 
Microscopic  examination,  however,  shows  that  these  hori- 
zontally lying  undulations,  which  occasionally  occur  on 
all  teeth,  are  not  due  to  a  deposit,  but  on  the  contrary  are 
caused  by  superficial  depressions.  Accordingly  the  con- 
dition is  a  genuine  hypoplasia.  Walkhoff  contributes  an 
interesting  case,  in  which  not  only  the  enamel  of  the 
crown,  but  also  the  whole  surface  of  the  root,  presented 


DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES.     193 

this  undulatory  appearance.  The  undulations  are  in  some 
cases  barely  visible,  while  in  other  cases  they  are  plainly 
formed.  The  latter  is  especially  true  when  the  dentin  is 
also  involved. 

I/acunse.  Bowl-shaped  lacunae  are  frequently  observed, 
especially  on  the  incisor  and  cuspid  teeth  of  both  the 
upper  and  the  lower  jaw  (Plate  19,  Figs.  1  and  2),  which 
are  either  pale  in  appearance  or  discolored  from  unclean- 
liness.  The  lacunae  may  be  the  size  of  minute  points  or 
larger,  and  they  may  be  confluent  and  have  irregular 
borders.  AVhen  these  lacun?e,  which  are  in  themselves 
striking  defects,  are  distributed  over  the  whole  tooth  sur- 
face, we  may  justly  speak,  as  did  the  older  authors,  of 
honey-comb  teeth. 

Two  or  three  lacunae  are  the  largest  number  usually 
observed,  although  they  occur  quite  frequently  in  larger 
numbers,  arranged  in  horizontal  rows  like  a  string  of 
pearls  (Plate  19,  Fig.  3).  A  number  of  such  pearl 
strings  are  sometimes  found  on  one  surface  of  the  tooth. 
Their  arrangement  in  stages  clearly  explains  the  nature 
of  their  origin,  which  may  be  traced  to  the  coordinating 
factors  of  disturbances  in  development  and  the  layer- 
like deposit  of  the  enamel. 

The  true  grooves  (Plate  19,  Figs.  4  and  5)  are  often 
bounded  by  edges  containing  variously-shaped  notches. 
This  condition  may  be  accepted  as  evidence  that  the 
grooves  were  preceded  by  union  of  the  lacunae,  which,  as 
was  described  above,  Avere  arranged  like  strings  of  pearls. 

Although  cases  in  which  tliere  is  partial  absence  of  the 
enamel  covering  occur  less  frequently  (Plate  19,  Fig.  6, 
and  Plate  20,  Figs.  1,  2,  3,  and  6),  yet  they  occasionally 
come  under  observation.  The  chewing  surface  and  a 
portion  of  the  lateral  walls  of  the  molars  as  well  as  from 
a  third  to  a  half  of  the  front  teeth  may  show  this  abnor- 
mality. A  clinical  picture  quite  frequently  met  with, 
consists  of  a  larger  or  smaller  portion  of  normal  enamel 
remaining  only  at  the  neck  of  the  tooth,  in  the  shape  of  a 
collar,  while  it  has  disappeared  from  the  rest  of  the  tooth. 
The  hypoplasia  may  indeed  be  of  so  high  a  grade  that  no 
13 


194    DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES. 

PLATE   19. 

Enamel  hypoplasise. 
Figs.  1  and  2.  Lacunae. 

Fig.  3.  Lacunse  arranged  in  rows  like  a  string  of  pearls. 
Figs.  4  and  5.  Grooves. 
Fig.  6.  Partial  absence  of  an  enamel  covering. 

PLATE  20. 

Enamel  liypoplasise. 
Figs.  1,  2,  3  and  6.  Partial  and  complete  absence  of  an  enamel  covering. 
Figs.  4  and  5.  Crescentic  defects.    (Hutchinson). 

enamel,  or  only  such  as  is  of  an  extremely  frail  texture, 
is  deposited. 

Hutchin.son  has  called  especial  attention  to  the  crescent- 
formed  defects  upon  the  central  incisors  (Plate  20,  Figs.  4 
and  5)  which  occur  in  congenital  syphilis.  He  has  been 
widely  misunderstood  and  his  theory  has  aroused  a  storm 
of  wrathful  opposition.  His  opponents  are  so  far  correct 
inasmuch  as  congenital  syphilis  may  occur  without  this 
symptom.  Hutchinson  does  not  deny  this  fact,  but 
simply  contributes  his  observation,  which  is  in  itself 
correct ;  namely,  that  this  sign  is  frequently  associated 
with  other  symptoms  of  congenital  syphilis. 

Dentin  may  be  the  seat  of  a  particular  form  of  hypo- 
plasia to  which  Baume  has  given  the  term  odontoporosis. 
This  process  consists  histologically  in  an  abnormal  substi- 
tution of  the  dentinal  tubules  by  globular  spaces.  Dentin 
which  has  thus  been  altered  naturally  more  readily 
undergoes  disintergration. 

The  therapy  of  hypoplasia  depends  upon  the  extent  and 
the  symptoms  of  the  condition.  Sharp  edges  as  well  as 
shallow  lacunse  which  because  of  discoloration  aifect  the 
appearance  of  the  teeth,  or  predispose  to  caries,  should  be 
ground  down  and  the  surface  polished.  In  the  less 
visible  regions  where  the  hypoplasia  cannot  be  removed 
by  grinding,  it  may  become  necessary  to  fill  the  defects 
with  gold,  amalgam,  or  cement.  In  the  visible  areas  it  is 
preferable  to  fill  with  porcelain.  Good  service  may  be 
obtained  by  applying  a  protecting  gold  cap  to  the  back 
teeth  when  they  lack  a  very  large  amount  of  enamel.   In 


Tab.19. 


Fig.l. 


Fig.2. 


Fig.J. 


Fig.  4-. 


Fig., 5. 


Fig.  6. 


Tab.20. 


Fiq.l. 


Eig.2. 


Fig.3. 


Fiq.  4 


Ficf.S. 


Fig.  a. 


PHYSIOLOGIC  ABRASION  OF  TOOTH  SUBSTANCES.  195 

a  similar  condition  of  the  front  teeth  large  pieces  of  por- 
celain are  employed,  and  it  may  indeed  even  become 
necessary  to  excise  the  tooth  and  replace  it  with  a  por- 
celain crown. 


ACQUIRED  DEFECTS  OF  THE  HARD  TOOTH 
SUBSTANCES. 

Acquired  defects  of  the  hard  teeth  include  :  Physiologic 
wearing  away  of  tooth  tissue ;  wedge-shaped  defects ; 
defects  on  the  labial  (buccal)  and  chewing  surfaces  of 
the  teeth. 

PHYSIOLOGIC  ABRASION  OF  TOOTH  SUBSTANCES. 

A  discussion  of  abrasions  really  belongs  to  the  realm 
of  physiology,  but  as  they  may  occasionally  develop  to 
such  an  extent  as  to  require  therapeutic  intervention,  we 
will  for  practical  reasons  treat  of  the  sub- 
ject in  this  place.  The  first  signs  of  wear- 
iug  away  are  noticed  in  the  upper  incisor 
teeth,  in  which  the  three  notches  soon 
disappear.  Later  the  horizontal  border, 
especially  of  the  lower  teeth,  becomes  so 
much  worn  that  the  dentin,  and  in  extreme 
cases  the  pulp,  becomes  exposed.  This  is 
especially  true  in  anomalies  of  articulation.       ^^g.  90.— An  up- 

■  -'  .  ,  .  .  per  incisor  tooth 

in  the  course  of  time  the  points  andapor-    of  an  ow  man, 

,.  r>  ,  1  r«  ,1  -J  J.      i.1       1  which    has    been 

tion  ot  the  crowns  oi  the  cuspici  teeth  also  ground  down  from 
wear  away.  However,  depending  upon  o^'^i^'^ry  ^^^^e- 
the  location  of  the  tooth,  the  lingual  or  the  buccal  surfaces 
may  wear  away  in  preference,  and  often  to  such  an  extent 
that  finally  only  a  lamella  of  paper  thickness  remains  (Fig. 
90).  In  the  normal  articulation  of  the  jaws,  the  upper 
front  teeth  tend  to  undergo  abrasion  on  the  lingual  aspect, 
while  in  protrusion  of  the  jaw  they  become  abraded  on 
the  labial  surface.  Of  the  j)icuspid  and  molar  teeth,  the 
cusps  are  worn  down  and  the  crowns  sacrifice  more  and 
more  of  their  height.     The  abraded  areas  of  individual 


196    DEFECTS  OF  THE  HARD   TOOTH  SUBSTANCES. 

PLATE   21. 

Fig.  1. — The  enamel  has  disappeared  from  the  whole  upper  surface 
of  a  cuspid  tooth.  The  dentine  has  been  destroyed  by  chronic  caries. 
The  root  shows  a  hypertrophy  of  the  cement. 

Fig.  2.^A  molar  tooth  of  an  older  man  which  has  been  worn  away 
by  mastication.     The  enamel  is  only  present  at  the  edges. 

Fig.  3. — A  middle  incisor  tooth  which  has  been  discolored  dark-brown 
by  extravasation  of  blood. 

Figs.  4,  5,  and  6. — Brown  and  green  tooth  deposits.  (Text,  page  191). 

teeth,  which    occupy  abnormal    positions,  present  many 
variations,  a  description  of  which  will  be  omitted  here. 

The  appearance  of  these  defects  may  be  distinguished 
from  other  tooth  affections  at  first  sight.  They  are  char- 
acterized by  the  above  described  localization  and  by  a 
hard  polished  surface  which  is  more  or  less  pigmented 
(Plate  21,  Fig.  2).      At  first,  the  patients  are    usually 


/ — ^■- 


Fig.  91.— Upper  illustration  :  a,  the  abraded  crown  of  a  molar  tooth,  seen 
from  above;  b,  the  darkly  discolored  substitution  dentin. 

Loiver  illustration  :  The  same  molar  tooth  on  longitudmal  section,  a,  per- 
sisting pulp;  5,  substitution  dentin. 

ignorant  of  the  existence  of  abrasions  because  symptoms 
are  absent.  Not  infrequently  however  the  exposure  of 
the  dentin  causes  sensitiveness  which  occasionally  results  in 
considerable  suffering.  Pain  also  occurs  when  _  irritation 
of  the  pulp  causes  the  development  of  a  pulpitis.      This 


Tab.  2  J 


Fig.  2. 


Fig.l. 


Fiff.3. 


1^1^.4 


Fig. 


Fig. a. 


WEDGE-SHAPED  DEFECTS.  197 

does  not  occur  very  frequently  however,  for  normal  teeth 
become  so  gradually  worn  away  by  normal  use  that  the 
pulp  has  sufficient  time  to  build  substitution  dentin 
(Fig.  91).  On  the  other  hand  pulpitis  is  more  likely  to 
develop  if  the  teeth  are  frail  in  structure,  and  therefore 
favor  rapid  destruction,  or  when  they  are  injured  by 
excesses. 

The  therapy,  since  we  know  the  exact  cause,  is  not  a 
difficult  one,  and  only  becomes  necessary  when  the  defects 
become  rapidly  enlarged.  If  a  soft  tooth  substance  is  in- 
volved, the  defect  is  shaped  for  the  retention  of  a  hard 
filling,  either  gold  or  amalgam,  according  to  circumstances, 
which  is  carefully  placed.  Such  a  surface  is  much 
more  resistive  than  the  dentin,  and  therefore  checks  the 
wearing  away  of  the  tissue.  In  certain  cases  porcelain 
fillings  are  also  very  servicable.  When  serious  pulpitis 
already  exists  it  is  necessary  to  devitalize  and  remove  the 
pulp,  and  then  fill  the  roots.  The  periodical  occurrence 
of  pain  in  abraded  bicuspids  and  molars,  which  can  no 
longer  be  improved  by  filling,  may  be  temporarily  allayed 
by  symptomatic  treatment.  This  may  be  done  by  re- 
peatedly cauterizing  the  chewing  surface  with  silver 
nitrate. 

WEDGE-SHAPED    DEFECTS. 

Wedge-shaped  defects  which  are  also  designated  as 
abrasions,  erosions,  or  denudations  develop  at  the  exposed 
portion  of  the  neck  of  a  tooth.  They  owe  their  name  to 
their  wedge-like  form,  wdiich  is  like  the  notch  made  by  a 
horizontal  cut  in  the  edge  of  the  enamel  with  a  file  (Fig. 
92  a).  This  condition  differs  essentially  from  carious 
defects  by  its  highly  polished  surface  which  shows  none 
or  very  little  discoloration.  Predilection  is  shown  for 
the  labial  surface  of  the  teeth  ;  the  lingual  or  the  inter- 
stitial   surfaces  are  only  rarely  involved. 

Originally  the  defect  is  very  minute,  and  nothing  is  felt 
when  an  instrument  or  the  finger  is  drawn  over  the  undu- 
lations toward  the  neck  of  the  tooth  excepting  an  insig- 
nificant  but   sharply  defined  notch.     The   slight  touch 


WEDGE-SHAPED  DEFECTS. 


of  the  finger  usually  causes  considerable  pain  and  it  is 
this  sensitiveness  for  which  the  patient  pays  the  dentist 
an  early  visit.  In  the  course  of  time  the  notches  increase 
in  depth  and  width,  and  finally  lead  to 
encroachment  upon  the  pulp  and  even  to 
the  breaking  off  of  the  crown.  An  inter- 
esting controversy  has  arisen  as  to  the 
development  of  these  defects.  It  has  been 
hitherto  assumed  that  these  defects  were 
due  to  purely  mechanical  causes,  such  as 
the  horizontal  rubbing  of  the  tooth  brush 
together  with  a  coarse  tooth  powder.  This 
o'oTh  action  is  supposed  to  attack  either  the 
vedge-    normal    neck  of  a  tooth    or  such   as    has 

shaped  defect  (a)     i  .    .  -,  ■,  •  i 

situated  on  the    been  injured  by  acids. 

labial  surface.         r^i^^^  ^j^g  normal  tooth  structures  (enamel 

or  dentin)  do  not  develop  typical  wedge-shaped  defects 
from  use  of  the  tooth  brush,  has  already  been  proved 
experimentally  by  M.  Bastyr  (Scheif 's  Handbuch),  and 
clinical  conditions  show  that  wedge-shaped  defects  may 


Fir.  92 
cuspid  t 
showing  a  wedge- 


FiG.  93. — A  wedge-shaped  defect  of  a  second  bicuspid  tooth  which  has  grown 
in  the  lingual  direction  from  the  tooth  row  and  which  cannot  therefore  be 
reached  by  the  tooth  brush. 


develop  on  such  teeth  as  can  not  be  reached  by  the 
brush  (Fig.  93).  Furthermore,  wedge-shaped  defects 
cannot  be  artificially  produced  by  rubbing  witii  a 
brush  tooth-substances  which  have  been  softened  with 
acids.  This  knowledge  Avas  obtained  by  means  of  the 
experiments    of    Bastyr.     That    investigator    expresses 


WEDGE-SHAPED  DEFECTS.  199 

his  observations  in  reference  to  the  probable  genesis 
of  this  disorder  as  follows:  "  Many  defects  are  due  to 
mechanical  influences  alone,  such  as  the  use  of  a  tooth- 
brush with  a  more  or  less  coarse  tooth  powder,  the  fric- 
tion of  the  lips  or  that  of  the  food  during  mastication. 
More  frequently,  however,  still  other  influences  occur. 
We  may  exclude  the  theory  that  acids  or  other  agents  dis- 
solve the  calcium  salts.  It  is  more  probable  that  pro- 
cesses are  concerned  which  dissolve  or  lessen  the  amount 
of  the  organic  ground  substance  of  the  tooth  ;  that  is, 
dentoidin.  Because  of  this  decrease  in  the  amount  of  the 
ground  substance,  the  lime  salts  become  disunited  and 
mechanically  disappear." 

The  author  agrees  with  the  pnnciple  theory  of  this 
thesis,  that  is,  that  in  the  main  other  influences  are  con- 
cerned and  that  acids  need  not  be  taken  into  consideration. 
He  also  believes  through  careful  tests,  which  he  has 
reported  elsewhere,  tliat  he  has  found  the  actual  agent 
which  injures  the  tooth  substance. 

In  order  to  understand  the  etiology  of  such  defects,  we 
must  refer  to  certian  bacteriologic  facts,  of  which  the  fer- 
ment, or  better,  enzyme,  activity  should  receive  chief  con- 
sideration, and  especially  the  action  of  the  proteolytic  or 
albumin  dissolving  enzyme  which  until  recently  has  not 
been  associated  with  this  condition.  In  speaking  of  the 
bacteria  of  the  mouth,  reference  is  frequently  and  incor- 
rectly made  to  their  peptonizing  activity,  while  as  a  matter 
of  fact,  recent  investigations  show  that  the  fluids  of  the 
mouth  are  alkaline  in  reaction  and  that  only  trypsins  are 
present.  (Pepsin  acts  only  in  an  acid,  and  trypsin  in  an 
alkaline  reaction.)  Nearly  all  bacteria  liquefy  gelatin, 
which  is  an  albuminous  body  ;  tliis  leads  us  to  wonder 
whether  or  not  the  albuminous  ground-substance  of  the 
teeth,  the  dentoidin,  is  liquefied  through  the  proteolytic 
enzyme  of  certain  bacteria  of  the  mouth,  and  whether 
through  this  process  the  tooth  substance  is  destroyed  even 
without  previous  decalcification.  Tlirough  chewing  and 
cleansing  the  resulting  jelly-like  substance  is  removed 
and  a  polished  surface  remains. 


200     DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES, 

Tests  have  been  made  upon  teeth  placed  in  bacterial 
cultures  and  which  were  acted  upon  for  a  long  time  by 
trypsin  which  was  obtained  from  the  pancreas.  In 
both  tests  a  partial  softening  of  the  hard  tooth  substances 
was  obtained  and  in  each  case  the  reaction  was  observed 
to  be  alkaline,  the  action  of  acids  being  thus  wholly 
excluded.  The  surfaces  of  teeth  which  have  become 
softened  are  naturally  more  prone  to  develop  wedge- 
shaped  defects  under  the  influence  of  mechanical  causes 
than  normal  teeth,  and  it  cannot  be  denied  that  processes 
similar  to  those  produced  artificially  occur  in  the  mouth. 
In  favor  of  this  supposition  is  the  chnical  fact  that  wedge- 
shaped  defects  are  not  rare  in  an  oral  cavity  with  rel- 
atively good  teeth  where  the  reaction  of  the  fluids  can  be 
demonstrated  to  be  more  strongly  alkaline  than  when  bad 
teeth  exist.  This  theory  is  furthermore  favored,  even 
though  conditionally,  by  the  localization  of  the  defects  at 
the  edge  of  the  gums  where  the  notches  between  the  neck 
of  the  tooth  and  the  gum  offer  the  bacteria  a  safe  recess 
for  their  development  and  propagation. 

As  a  prophylaxis  the  patient  should  be  advised  to  brush 
his  teeth  in  a  vertical  direction.  Therapeutically,  silver 
nitrate  is  used  to  the  greatest  advantage.  It  acts  as  a 
most  satisfactory  analgesic,  and  at  the  same  time  lessens 
the  susceptibility  of  the  injured  areas  to  the  action  of  the 
above  described  trypsin  by  forming  albuminous  nitrate 
of  silver,  as  well  as  chlorid  of  silver,  etc.,  which  are 
insoluble  combinations  and  unlike  the  organic  dental  sub- 
stance. If  the  amount  of  substance  lost  be  extensive,  the 
defect  must  be  filled  with  gold,  porcelain,  amalgam,  or 
guttapercha.  Contrary  to  the  observations  of  most  author  o, 
we  find  that  drilling  the  base  of  a  wedge-shaped  defect 
occasions  but  little  pain.  This  is  remarkable  considering 
that  only  a  slight  touch  will  cause  severe  pain. 


CARIES  OF  THE  TEETH,  201 

DEFECTS  OF  THE  LABIAL  (BUCCAL)  AND  MASTICATING 
SURFACES  OF  THE  TEETH. 

Aside  from  the  wedge-shaped  defects,  peculiar  polished 
cavities  are  observed  in  other  areas  of  the  enamel.  Their 
origin  is  still  in  the  dark  and  therefore  Baume  sums  them 
up  under  the  title  :  "Abrasions  from  insufficiently  under- 
stood causes."  To  this  class  belong  the  heart  and  egg- 
shaped  labial  defects  on  the  front  teeth  which  have  been 
described  by  Walkhoff";  and  the  extensive  abrasions  which 
occur  on  the  labial  surface  of  the  whole  tooth  row,  as  was 
described  by  Baume.  If  such  defects  occur  on  the  masti- 
cating surfaces  of  the  bicuspid  and  molar  teeth,  they  are 
termed  by  Baume  necrosis  ebons.  All  of  these  defects 
run  a  chronic  course  accompanied  by  a  more  or  less 
marked  hardening  and  polishing  of  the  surface,  and  a 
pigmentation,  which  may  include  all  the  varying  shades 
between  light  yellow  and  black. 

The  therapy  differs  in  no  way  from  that  of  the  hypo- 
plasias or  the  wedge-shaped  defects. 

CARIES  OF  THE  TEETH. 

Of  all  tooth  aff^ections  caries  is  the  most  frequent  and 
in  our  locality  hardly  more  than  1  per  cent,  of  all  adults 
possess  teeth  which  are  absolutely  free  from  this  con- 
dition. Caries  of  the  teeth  are  recognized  by  the  fact 
that  in  certain  areas  of  the  dental  tissues,  depending  upon 
the  grade  of  the  condition,  a  discoloration,  softening  and 
loss  of  substance  occur.  Caries  does  not  affect  all  teeth 
alike.  Attention  has  been  called  to  i\\e  frequency  of  caries, 
depending  upon  the  location  of  the  teeth,  by  a  large  num- 
ber of  authorities,  amongst  them  Linderer,  Rose,  Berten, 
Lippschitz,  Port  and  others.  J.  Scheff"  has  recently  pub- 
lished a  very  complete  table  of  the  statistics  of  the 
frequency  of  caries,  which  is  especially  valuable  because 
reference  is  also  made  to  incipient  caries ;  the  other 
authorities  (for  example  Linderer)  probably  resorted  to 


202    DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES. 

their  table  of  extractions  for  the  source  of  their  statistics, 
a  fact  which  made  them  comparatively  worthless. 

The  following  figures  of  J.  Scheff  show  the  relative 
frequency  of  the  occurrence  of  caries  in  a  thousand  cases  : 

The  teeth  involved.  Frequency  of  caries        Frequency  of 

in  the  upper  jaw.  caries  in  the 

lower  jaw. 

Incisor  1 110  15 

Incisor  II 95  17 

Cuspid, 63  22 

Bicuspid  1 87  41 

Bicuspid  II 80  50 

Molar  1 104  95 

Molar  II 72  82 

Molar  III 36  31 

647  353 

Accordingly  out  of  1000  carious  teeth  which  were 
examined,  647  occurred  in  the  upper  jaw,  and  353  in  the 
lower.  This  is  not  the  place  to  discuss  the  cause  of  the 
greater  frequency  of  caries  of  teeth  in  the  upper  jaw. 
The  old  theory  that  the  saliva,  which  nearly  always  con- 
stantly bathes  the  teeth  of  the  lower  jaw,  has  an  inhibit- 
ing influence  on  putrefactive  processes  no  longer  suffices 
as  an  explanation,  since  Miller  has  demonstrated  that  the 
saliva  possesses  no  bactericidal  agency.  We  are  equally 
unable  to  explain  the  enormous  differences  in  the  fre- 
quency of  caries  between  the  individual  teeth  in  the  same 
jaw  ;  for  example,  in  the  upper  jaw  the  first  incisor  shows 
a  frequency  of  110,  the  first  molar  104,  while  the  cuspid 
and  the  wisdom  teeth  show  the  lowest  figures,  their  fre- 
quency being  respectively  63  and  36.  This  may  lead 
one  to  associate  a  causal  relationship  between  the  periods 
of  eruption  or  the  deposit  of  the  tooth  germ,  and  a  sus- 
ceptibility to  caries.  However  this  question  has  not  as 
yet  been  satisfactorily  solved. 

Aside  from  these  teeth  which  are  more  or  less  prone  to 
undergo  caries,  decided  areas  of  predilection  occur  on  the 
individual  teeth  to  which  the  diagnostician  must  pay 
special  attention.     The  fissures  in  the  molar  and  bicus- 


CARIES  OF  TEE  TEETH.  203 

pid  teeth  serve,  especially  when  they  are  abnormally 
formed,  that  is,  composed  of  clefts  and  holes,  as  retention 
areas  for  the  putrefactive  bacteria,  and  the  food  remnants 
which  form  nutritive  material.  The  most  frequent  seats 
for  the  development  of  the  carious  process  are  not  only  the 
distal  and  mesial  grooves  and  the  central  fossa  between 
the  cusps  of  the  chewing  surface,  but  also  the  buccal 
groove  of  the  lower  molars  which  terminates  in  the  fora- 
men coecum  and  to  a  less  extent,  the  lingual  groove  of 
the  upper  molars.  In  a  similar  manner  the  foramina 
coeca,  which  are  situated  on  the  lingual  aspect  of  the  front 
upper  incisors,  and  preferably  the  lateral  ones,  are  also 
prone  to  become  the  seat  of  this  process.  Likewise  the 
approximal  surfaces  of  the  teeth  show  a  predilection  to 
become  involved,  because  of  the  tendency  of  food  to  be 
retained  in  that  region,  which  subsequently  tends  to 
undergo  fermentation.  On  the  other  hand  all  smooth 
accessible  surfaces  which  are  kept  clean  either  artificially 
by  means  of  a  brush,  or  naturally  through  the  act  of 
mastication  and  by  means  of  the  tongue,  are  less  subject 
to  carious  changes.  Herein  lies  the  most  probable  expla- 
nation for  the  diflPerence  in  the  frequency  of  caries  in  the 
various  divisions  of  the  teeth,  for  as  we  know  caries 
attacks  most  frequently  the  molars  which  possess  many 
more  depressions  than  the  front  teeth  with  their  flat  sur- 
faces. However,  this  explanation  does  not  suffice  for  all 
cases.  The  etiology  really  interests  us  the  most,  for  with- 
out a  thorough  knowledge  of  it,  all  protective  hygiene  is 
illusory. 

A  certain  group  of  etiologic  factors  are  termed  more  or 
less  correctly,  jyredisposing  influence.'^.  These  consist  of 
anomalies  of  the  enamel,  and  anomalies  in  the  position 
of  the  teeth  and  of  articulation.  There  is  also  no  doubt 
but  that  a  significant  influence  upon  the  development  of 
caries  must  be  ascribed  to  heredity  and  race.  The  influ- 
ence of  civilization  should  be  considered  in  so  far  as  its 
food  is  ])oor  in  lime  salts  and  because  it  is  served  in  the 
form  of  a  pasty  soft  mass,  on  account  of  which  abnormal 
processes  of  fermentation  arise  in  the  mouth.     It  must  be 


204    DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES. 

also  considered  that  this  soft  consistency  of  the  food  is 
harmful  because  it  need  not  be  chewed  and  in  consequence 
the  normal  nutrition  of  the  teeth  suffer  from  inactivity. 

The  frequency  of  caries  in  those  who  dwell  in  cities  is 
of  especial  interest,  for  amongst  them  the  poor  show  a 
much  greater  predisposition  to  caries  than  the  wealthy. 
The  reason  for  this  is  simply  that  in  poor  people  the  "  mal 
nourris,  mal  loges,  and  mal  vetus,"  througli  disturbances 
of  the  general  health  especially  during  the  first  year  of 
life/  cause  a  faulty  excretion  of  the  calcium  salts,  with 
the  consequent  development  of  poor  tooth-substances. 
Furthermore  poor  patients  can  not  afford  to  consult  a 
dentist  for  a  rational  prophylactic  treatment  of  these 
developmental  defects  and  for  cleansing  of  the  oral  cavity. 

All  of  these  more  or  less  correct  and  known  predis- 
posing causes  were  already  recognized,  aj^art  from  the 
exciting  causes,  at  the  time  of  J.  Tomes  and  are  the  influ- 
ences in  which  we  are  especially  interested. 

With  reference  to  the  history  of  the  etiology  of  caries 
we  will  only  briefly  refer  to  a  small  portion  of  the  works 
which  may  be  looked  upon  as  the  predecessors  of  the 
modern  chemical  and  parasitic  theory. 

A  ])v\m[tive 2:>cirasite  theory  was  recognized  even  by  the 
older  physicians.  According  to  it  small  worms  were 
believed  to  bear  a  causal  relationship  to  caries.  In  1663, 
Leeuwenhoek  made  a  more  thorough  investigation  of  this 
subject,  the  results  of  which  were  published  in  the 
"  Transactions  of  the  Royal  Society,"  His  contribution 
is  reproduced  here  in  his  own  words  in  order  to  show 
with  what  remarkable  exactness  he  recognized,  with  at 
that  time  still  imperfect  optical  methods,  the  wonderful 
microscopic  conditions  of  the  mouth. 

Concerning  this  subject  he  wrote  as  follows  :  "  Although 
I  keep  my  teeth  very  clean,  yet  when  I  look  at  them 
with  a  magnifying  glass  I  observe  in  the  spaces  between 
them  a  white  mass  which  looks  like  moistened  flour.     I 

lit  is  known,  according  to  WalkliofiF  and  other  authorities,  that  the 
condition  of  health  during  the  first  year  of  life  has  a  decided  influence 
upon  the  density  of  the  hard  tooth-substance. 


CARIES  OF  THE  TEETH.  205 

mixed  this  substance  with  some  saliva  and  rain  M'ater 
■which  contained  no  bacteria,  and  observed  under  the 
microscope  that  this  mass  contained  minute  Hving  organ- 
isms which  only  rarely  showed  movement.  I  was  able  to 
distinguish  three  varieties  of  this  micro-organism.  The 
largest  were  present  in  the  smallest  numbers  but  their 
movement  was  equally  as  strong  and  active  as  that  of  a 
white  pike  swimming  in  a  lake.  The  smaller  micro- 
organisms existed  in  large  numbers  and  were  character- 
ized by  a  skipping  movement.  The  third  and  smallest 
variety  were  partly  oval  and  partly  round  in  form  and 
moved  with  the  agility  of  a  swarm  of  flies  which  are 
wildly  dashing  to  and  fro  in  a  small  enclosed  space. 

Aside  from  these  forms  of  micro-organisms,  I  also 
noticed  a  number  of  strise  and  threads  of  varying  length 
yet  of  equal  thickness,  some  of  which  were  straight  and 
others  curved.  They  lay  upon  each  other  and  seemed  to 
possess  neither  motion  or  life." 

In  the  same  year  Ficinus  presented  his  observation  that 
caries  of  the  teeth  was  due  to  the  action  of  minute  organ- 
isms in  the  mouth  which  he  called  wfusorke  (dentlcola). 
He,  therefore,  accepted  the  old  purely  parasitic  theory 
which  reaches  back  to  the  time  of  Scribonius.  This 
theory  was,  however,  not  generally  adopted  in  spite  of  the 
fact  that  contributions  were  made  to  it  from  time  to  time 
by  skilled  investigators,  like  Klenke,  who  claimed  a 
profoeoecus  dentalis  as  the  exclusive  exciting  cause  of 
caries. 

Then  came  the  observation  of  Balm  that  caries  was  a 
purelv  chemical  process  which  consists  of  decalcification 
of  the  hard  tooth-substances  by  means  of  acids.  It  was 
concluded  from  this  observation  that  defects  similar  to 
caries  could  be  produced  by  allowing  certain  acids  to  act 
upon  extracted  teeth.  It  was  believed  that  the  acids 
tliemselves  M'ere  either  introduced  from  without  through 
food,  or  developed  from  fermentation  processes  of  re- 
tained food  remnants.  The  supposition  was  also  expressed 
that  the  tooth-substance  wag  destroyed  by  pathologically 
altered  j^nd  acid-reacting  secretion  of  the  gums  and  the 


206     DEFECTS  OF  THE  HARD   TOOTH  SUBSTANCES. 

oral  mucous  membrane  (Wedl),  as  well  as  through  oral 
fluids  which  contain  abnormal  constituents  (Scheff). 

To  this  purely  parasitic  and  purely  chemical  explana- 
tion of  the  cause  of  caries,  is  added  in  more  modern  times 
another,  the  chemicoparasitic  theory.  The  name  chemico- 
parasitic  is  not  altogether  correct  for  as  a  matter  of  fact 
the  term  parasitism  implies  the  chemical  processes 
which  result  from  the  very  beginning.  When  we  speak 
of  bacterial  diseases  we  never  think  of  the  physical  action 
of  the  microorganisms  but  instead  only  of  the  chemical. 
The  various  bacteria  are  moreover  only  pathogenic  when 
they  possess  the  property  of  forming  chemical  substances 
within  the  organism  which  are  in  any  way  injurious  to  it. 
When  disease  follows  infection  with  the  bacillus  of  tetanus 
the  diphtheritic  bacillus,  or  any  variety  of  pyogenic  bac- 
teria, we  know  with  certainty  that  the  symptoms  which 
arise  are  due  to  specific  poisons,  and  that  the  latter  and 
the  alexin  or  the  present  antitoxin  which  eventually  de- 
velop are  chemical  agents.  However,  one  would  not  refer 
to  the  resulting  condition  as  chemicoparasitic,  but  rather 
as  parasitic.  The  large  number  of  more  or  less  well- 
known  bacteria  in  the  mouth,  which  injure  the  dental  tis- 
sue through  any  sort  of  process,  must  be  absolutely  con- 
sidered as  pathogenic  according  to  the  above  statements. 
As  soon  as  we  recognize  them  to  be  of  pathogenic  nature, 
a  smaller  or  greater  amount  of  chemical  action  is  of  course 
understood.  The  process  differs  somewhat  when  acids, 
such  as  fruit  acids  administered  in  the  grape  cure,  act 
upon  the  tooth-substance,  and  when  the  oral  bacteria 
secondarily  affect  and  destroy  the  tooth  cartilage.  In 
such  a  case  to  be  sure,  we  have  a  combination  of  indepen- 
dent chemical  and  parasitic  processes.  For  the  sake  of 
a  clearer  conception  of  these  processes  which  are  so  easily 
misunderstood,  the  author  suggests  that  in  the  future  the 
terra  chemiGoparasitic,  be  reserved  only  for  such  carious 
processes  in  which  the  decalcification  of  the  teeth  is  due 
to  other  acids,  than  those  generated  in  the  month  by  bac- 
teria. It  is  logical,  therefore,  to  consider  all  ordinary 
carious  processes,  even  when  associated  with  the  forma- 


CAMIES  OF  THE  TEETH.  207 

tion  of  acids  by  the  carbohydrates  in  the  mouth,  as  purely 
parasitic  since  they  are  due  to  the  action  of  bacteria. 

The  majority  of  investigators  were  unknowingly  ad- 
herents of  the  purely  parasitic  genesis.  This  is  indicated 
by  their  zealous  attempts  in  search  of  the  specific  cause 
of  caries.  Some  believed  caries  to  be  due  to  a  single 
species,  and  indeed  it  was  formerly  agreed  by  nearly  all 
that  the  cause  was  the  leptothrix  buccalis,  a  property  first 
attributed  to  this  micro5rganism  by  Leber  and  Rotten- 
stein,  and  later  also  by  Neumann,  Erdl,  Schrott  and 
others.  Ad.  Weil  considered  the  process  to  be  of  a 
different  nature.  He  believed  that  this  hyphomycetes 
drilled  through  the  superficial  coat  of  the  enamel  and 
then  through  the  enamel  in  order  to  reach  the  dentin.  In 
more  recent  times,  the  theory  of  a  specific  excitant  of 
caries  has  received  but  little  attention,  but  the  observation 
of  Sieberth  seems  again  to  speak  in  its  favor.  He  claimed 
to  have  found  streptococci  almost  exclusively  in  the  deeper 
layers  of  carious  dentin.  By  far  the  greatest  number  of 
the  bacterio-odontologists  of  the  newer  school  accept  the 
view  promulgated  by  Black,  Miles  and  Underwood  in 
1881.  According  to  these  observers  the  carious  process 
is  due  to  the  formation  of  acids  by  a  large  number  of 
microorganisms  which  lie  between  and  on  the  teeth. 
Credit  is  due  Miller,  whose  work  on  this  subject  is  known 
by  all,  for  giving  it  the  experimental  support  which  it 
needed  to  make  it  popular.  When  the  most  important 
of  comparatively  few  results  of  special  investigations,  as 
regards  the  presence  of  multiple  excitants  of  caries,  are 
considered  we  may  draw  the  following  conclusions.  Iso- 
lation of  the  bacteria  in  question  was  usually  undertaken 
from  the  deeji,  comparatively  intact,  ])ortion  of  the  dentin 
which  lies  below  the  infected  focus,  in  order  to  exclude 
the  saproj)hytic  and  such  other  microorganisms  as  may 
happen  to  be  present  by  chance.  In  this  manner  Galippe 
and  Vignal  found  six,  Jung  eleven,  and  Goadby,  as  well 
as  Miller,  a  number  not  exactly  determined.  By  com- 
paring, on  close  observation  all  of  these  exact  and  pains- 
taking investigations,  we  became  impressed  with  the  vast 


208     DEFECTS  OF  THE  HARD   TOOTH  SUBSTANCES. 

divergence  in  the  results.  The  conditions  found  seem, 
therefore,  to  prove  that  caries  is  not  dependent  upon  one  or 
several  varieties  of  specific  excitants,  but  is  probably  more 
likely  to  be  due  to  the  majority  of  the  ordinary  bacteria 
found  in  the  oral  cavity.  As  concerns  the  more  minute  de- 
structive processes,  the  formation  of  acids  is  to  be  especially 
considered.  According  to  Miles  and  Underwood,  acids 
are  excreted  directly  from  the  organic  tooth-substances. 
AVe  cannot  agree  with  this  observation,  on  the  ground 
that  bacteria  never  form  acids  from  albuminous  substances, 
to  which  class  the  organic  substances  of  the  teeth  belong. 
The  anther  fully  agrees  with  the  view  of  K.  Jung,  who 
states  "  that  it  is  hard  to  understand  the  observation 
made  by  certain  writers  that  the  bacteria  generate  acids 
by  dissolving  the  albuminous  tooth-substances  through 
their  peptonizing  properties."  Like  in  the  reagent  glass, 
acids  can  only  be  formed  in  the  presence  of  carbohy- 
drates. Bacteria  cause  the  formation  of  acids  as  soon  as 
carbohydrates  are  added  to  the  nutritive  media.  We 
may  judge  of  the  number  of  acid-forming  bacteria  in 
nature  from  the  fact,  for  example,  that  dough  or  similar 
confections  when  exposed  to  the  air  soon  become  sour. 
It  is  the  same  two  carbohydrate  elements  in  these  sub- 
stances, starch  and  sugar,  which  when  introduced  into 
the  mouth  as  food,  remain  there  in  small  or  large  quanti- 
ties, especially  in  the  depressions  of  the  teeth,  and  soon 
ferment  because  of  the  favorable  temperature  and  the 
presence  of  masses  of  micro5rganisms.  One  reads  con- 
stantly of  lactic  acid  being  thus  generated,  but  aside  from 
it  traces  of  formic,  propionic,  butyric  and  acetic  acid  are 
also  found.  The  outer  coat  of  the  enamel  is  first  attacked, 
if  it  is  present,  and  eventually  the  enamel  or  the  dentin 
is  involved.  The  clinical  observation  that  bakers  and 
confectioners,  in  whose  mouths  flour  and  sugar  dust  are 
deposited,  are  subject  to  rapid  decay  of  their  teeth  is 
explained  by  the  fact  that  the  developing  acids  destroy 
the  outer  cuticle  of  the  enamel  to  a  large  extent.  How- 
ever it  is  stated  in  all  text-books  that  the  outer  enamel 
coat  is  absolutely  resistant  to  acids  and  alkalies.      Since 


CARIES  OF  THE  TEETH.  209 

this  claim  is  obviously  a  contradiction  to  the  above 
clinical  phenomenon,  the  writer  decided  to  investigate 
this  fundamental  and  highly  important  question.  The 
derivation  of  a  satisfactory  explanation  from  the  litera- 
ture was  excluded  from  the  beginning,  for  practically 
nothing  is  known  of  the  chemistry  of  the  outer  cuticle  of 
the  enamel. 

We  can  only  reproduce  here  excerpts  of  experiments 
undertaken,  which  were  published  in  full  in  the  "  Oesterr- 
ungar,  Vierteljahrschrift  fiir  Zahnheilkunde  (1902,  Xo. 
IV)."  A  large  number  of  acids  were  concentrated  and 
diluted,  and  their  action  tested  both  upon  the  outer  enamel 
cuticle  and  on  the  enamel  itself.  The  unequivocal 
results  of  the  action  of  the  acids  were  as  follows  :  In  a 
shorter  or  longer  time  the  outer  covering  of  the  enamel 
became  decolorized  and  occasionally  discolored.  At  the 
same  time  it  became  swollen,  formed  air  containing  vesi- 
cles, and  was  finally  dissolved  from  the  enamel. 

From  these  facts  it  is  learned,  contrary  to  all  former 
hypotheses,  that  the  enamel  cuticle  is  strongly  influenced 
and  severely  injured  by  acids.  However,  the  whole 
membrane  is  not  completely  destroyed,  but  a  portion 
remains  behind  in  the  form  of  more  or  less  large  floeculi 
that  are  the  residue,  which  cannot  ])e  loosened  even  by 
the  strongest  mineral  acids.  Tiiis  condition  has  led  to 
the  statement  that  it  was  impossible  to  thus  destroy  the 
whole  enamel  membrane.  These  experiments  have  shown 
that  the  enamel  membrane  can  be  destroyed  by  acids, 
including  such  as  are  formed  in  the  mouth  from  the  carbo- 
hydrates. A  certain  leugth  of  time  and  a  certain  degree 
of  concentration  is,  however,  necessary  for  this  purpose. 

It  was  furthermore  observed  on  exauiination  that 
organic  as  Avell  as  inorganic  acids  brought  forth  trans- 
verse striae  on  the  enamel  prisms.  This  observation,  how- 
ever, did  not  harmonize  with  the  perfectly  correct  claim 
that  there  can  be  "  no  caries  without  acids,"  for  we  have 
frequently  had  occasion  to  obtain  dental  caries  without 
any  traces  of  transverse  strite.  This  led  to  the  belief  that 
possibly  still  other  factors  are  concerned  in  the  develop- 
14 


210  DEFECTS  OF  THE  TIARD  TOOTH  SUBSTANCES. 

ment  of  caries  which  have  not  as  yet  been  appreciated ;  for 
instance,  the  enzymatic  action  of  such  bacteria  as  liquefy 
gelatin,  that  is,  that  proteolytic  (albumin  dissolving) 
action  which  we  have  already  discussed  in  connection 
with  the  etiology  of  the  wedge-shaped  defects.  Such  an 
enzymatic  activity,  which  is  brought  about  by  bacterial 
trypsin  in  an  alkaline  reaction,  acts  by  dissolving  the 
dental  tissues.  This  is  readily  demonstrated  by  the 
action  of  animal  trypsin  upon  tlie  tooth-substances.  This 
observation  is  strongly  supported,  as  none  less  than 
Arkovy  and  Miller  have  already  expressed  the  presump- 
tion that  the  development  of  caries  in  the  presence  of  an 
alkaline  media  may  occasionally  be  associated  with  other 
influences.  Also  in  favor  of  our  supposition  is  the  fact 
that  caries,  even  though  in  a  more  chronic  form,  occurs 
when  the  fluids  of  the  oral  cavity  are  alkaline  in  reaction. 
If,  then,  we  again  briefly  review  the  points  of  the  etiology 
of  caries,  we  reach  the  following  two  conclusions  : 

Tooth  caries  depends  chiefly  upon  purely  jxirasitie 
processes,  and  as  far  as  is  known,  these  act  in  two  ways. 
The  first  and  more  frequent  consists  in  the  formation  of 
acids  by  the  action  of  the  microorganisms  of  the  mouth 
upon  the  remnants  of  the  carbohydrates  from  the  food 
which  are  attached  to  the  teeth.  These  acids  dissolve 
the  calcium  salts  of  the  teeth.  The  organic  residue,  as  is 
the  case  in  all  putrefactive  processes,  is  then  destroyed  by 
the  bacteria,  probably  by  peptonization.  The  second  and 
rarest  form  of  this  process  presumably  leads  to  a  more 
chronic  form  of  caries  which  occurs  in  an  alkaline 
reaction.  Contrary  to  the  former,  the  organic  ground 
substance  is  first  destroyed,  and,  it  is  highly  probable  that 
this  disintegration  is  brought  about  by  the  bacterial 
trypsin.  As  soon  as  the  organic  connective-tissue  is  dis- 
solved the  calcium  salts  fall  out  secondarily.  It  is  not 
impossible  that  in  the  ordinary  form  of  caries  both  of 
these  processes  act  alternately. 

Aside  from  the  above  described  injuries  caused  by  bac- 
teria, it  is  necessary  to  again  discuss  here  the  purely 
chemical  actions  upon  the  teeth  to  which  reference  has 


CARIES  OF  THE  TEETH.  211 

been  previously  made.  This  factor  depends  upon  acids 
which  have  been  introduced  into  the  mouth  from  without 
(grape  or  lemon  cures),  or  such  as  arise  in  the  larger  or 
smaller  glands  of  the  mouth  on  account  of  disease.  The 
softening  which  is  thus  produced  can  hardly  be  called 
caries,  and  it  is  reported  at  this  time  simply  to  call  atten- 
tion to  it. 

The  objective  symptoms  caused  by  the  beginning  of 
caries  in  the  enamel  are  as  follows.  According  to  J. 
Tomes,  two  varieties  are  to  be  distinguished,  concerning 
which  he  writes  :  "  If  the  disease  begins  in  a  fissure  on 
the  masticating  surface  or  in  a  depression  in  the  crown  of 
a  tooth,  the  first  sign  of  the  presence  of  caries  is  a  very 
dark  spot.  If,  however,  a  surface  is  attacked  which  is 
free  of  indentations  or  fissures,  the  affected  part  loses  its 
transparency  and  becomes  dull  and  white.  The  white 
color  gradually  turns  to  an  ashy  gray  or  slate  color  and 
finally  is  substituted  by  a  more  or  less  dark  brown  dis- 
coloration." Since  this  process  in  the  fissures  is  concealed 
by  the  discoloration,  or  complicated  with  dentinal  caries,  it 
is  more  satisfactorily  studied  on  the  flat  surfaces. 

Caries  always  begins  as  a  white  lusterless  speck  ;  this 
discoloration  is  due  to  the  fact  that  bacteria  penetrate  the 
superficial  enamel  membrane  and  alter  its  composition. 
Later  the  superficial  prismatic  layer  becomes  split  and  the 
enamel  pigmented.  The  enamel  which  is  at  first  opaque 
and  smooth  is  soon  felt  with  the  sound  to  be  rough  on 
account  of  a  loss  of  substance.  Heider  called  attention 
in  "  Wedl's  Pathology  "  to  the  fact  that  these  specks  may 
be  discolored  dark  to  a  varying  degree,  and  speaks  con- 
cerning this  matter  as  follows  :  "The  various  grades  of 
colors  do  not  represent  different  stages  of  the  process, 
but  characterize  diiferent  modifications  of  it.  Indeed,  the 
lighter  the  speck,  the  deeper  is  the  destruction  and  the 
more  rapid  the  process.  The  darker  the  color,  the  more 
limited  and  circumscribed  is  the  discolored  portion  of  the 
enamel  and  the  slower  the  process."  Accoi'ding  to  these 
statements,  the  discoloration  served  a  diagnostic  purpose 
in  the  sense  that  dark  pigmentation  indicates  the  presence 


212  DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES. 

of  caries  chronica,  and  specks  which  remain  light  in  color, 
caries  acuta.  It  is  usually  stated  in  the  literature  that 
this  dark  pigmentation  really  represents  a  retarded  cari- 
ous process,  and,  on  the  other  hand,  the  light  coloration 
a  rapid  progress.  According  to  the  author's  observations, 
however,  this  supposition  is  wholly  erroneous,  for  the 
pigmentation  does  not  seem  to  be  the  cause  but  rather 
the  sequel  of  a  chronic  course.  This  is  proved  by  the 
fact  that,  for  example,  when  a  pale  acute  carious  focus, 
situated  on  a  proximal  surface,  has  been  changed  to  the 
chronic  form  by  extraction  of  the  bordering  tooth,  it 
shows  a  tendency  after  a  time  to  become  dark  in  color. 
The  simple  explanation  of  the  problem  is  that  uncleanly 
foreign  matter  of  any  sort  in  the  aifected  focus  is  dis- 
charged by  the  rapid  progression  of  the  softening  process, 
while  it  becomes  fixed  for  a  longer  time  when  the  process 
is  slow.  Therefore,  the  cause  and  aifect  have  been  mis- 
taken for  each  other. 


Fig.  94.— a,  molar  tooth  with  undermining  caries,  and  (b)  with  penetrating 

caries. 

Caries  of  the  enamel  is  recognized  microscopically  by 
the  fact  that  the  tissue  loses  its  transparency.  It  appears 
more  or  less  darkly  pigmented,  and  the  enamel  prisms 
show  transverse  strise,  and  are  destroyed  in  small  areas. 
Masses  of  bacteria  are  seen  in  the  lacunae  of  the  enamel. 
Frequently,  however,  none  of  these  signs  are  noted,  the 
enamel  being  simply  diffusely  discolored,  and  the  inter- 
prismatic  cement  substance  more  swollen  than  is  the  case 
in  the  normal  condition. 

If  the  dentin  is  involved,  the  process  often  spreads 
underneath  the  enamel  in  a  lateral  direction,  so  that  the 
latter  partially  covers  the  defect,  Fig.  94  a.  Miller  applied 


CARIES  OF  THE  TEETH. 


213 


the  term  undermining  caries  to  this  condition.  It  is 
especially  prone  to  occur  in  the  cases  in  which  interglobu- 
lar spaces  are  spread  out  in  the  periphery  of  the  dentin. 
Sometimes  caries  follows  directly  the  course  of  the  den- 
tinal tubules,  and  peuetrates  rapidly  into  the  neighborhood 
of  the  pulp  (Fig.  94  6),  which  is  called  penetrating  caries. 
The  most  striking  symptom  seen  on  microscopic  exami- 
nation (see  Fig.  95)  in  caries  of  the  dentin  is  the  presence 

rpTi 


Fig.  95.— Caries  of  the  dentin:  a,  dentinal  tulniles  without  any  or  only  a  few 
fungi ;  h,  the  tubules  are  here  more  crowded  with  fungi  which  cause  them  to 
be  somewhat  dilated  ;  c,  the  normal  structure  of  the  dentin  has  been  destroyed 
by  a  fusion  of  irregular  spaces  which  are  filled  with  bacteria.  Longitudinal 
section. 

of  bacteria  to  a  certain  extent,  in  both  the  dentinal  tubules 
and  the  interglobular  spaces.  These  microorganisms 
include  cocci,  bacilli,  filaments  or  mixed  infections.  Under 
the  influence  of  these  microorganisms  the  tubules  become 
wider  at  the  expense  of  the  dentinal  ground  substance. 
Club-like  thickenings  arise  in  scattered  areas,which  becom- 
ing confluent  with  similar  formations  in  the  neighbor- 
hood, cause  the  dentin  to  become  more  and  more  perforated 
and  finally  destroyed.  As  the  healthy  tissue  is  approached 
the  conditions  become  more  normal,  that  is,  the  dentinal 
tubules  are  slightly  or  not  at  all  increased  in  width  and 
contain  a  less  number  of  fungi  micro()rganisms,  and  in  fact 
in  certain  areas  they  harbor  only  a  few  fungi. 

The  walls  of  the  dentinal  tubules,  that  is,  the  sheaths 
of  Neumann,  which  arc  filled  with  bacteria,  are  thickened. 


214  DEFECTS  OF  THE  HARD  TOOTH  SUBSTANCES. 

They  have  the  appearance  of  being  swollen,  which  is  best 
seen  in  a  cross  section  of  the  tubules,  like  that  shown  in 
Fig.  96.  At  the  border  between  the  normal  and  carious 
dentin,  rows  of  small  rods  and  sphericles  are  often  noted, 
which  Miller  believes  consist  of  lime,  because  they  are 
rapidly  dissolved  by  sulphuric  acid. 


Fig.  96.— Caries  of  the  dentin.  The  pale  rings  are  the  cross  sections  of  the 
sheaths  of  Neumann,  which  are  swollen,  dilated,  and  filled  with  bacteria. 
Cross  section. 

Caries  attacks  the  cementum  when  the  roots  are  exposed. 
Caries  of  the  roots  of  the  teeth  is  distinguished  from  that 
of  the  other  structures  by  less  amount  of  pigmentation,  and 
by  the  fact  that  the  defects  usually  cover  a  larger  portion 
of  the  surface,  and  are  less  likely  to  penetrate  very  deeply. 

THE  ZONES  OF  CARIES. 

Four  zones  are  discernable  on  longitudinal  or  cross 
section  of  carious  teeth.     They  are : 

Zone  of  transparency. 

Zone  of  opacity. 

Zone  of  softening. 

Zone  of  disintegration. 

A    suitable   incision    will  show  a  transparent  dentinal 

layer  (Plate  22  a.)  which  occurs  in  caries  of  the  enamel, 

and  follows  in  the  form  of  a  tapering  cone  the  course  of 

the  dentinal  tubules  toward  the   pulp.     In  caries  of  the 


THE  ZONES  OF  CARIES.  215 

dentin  this  layer  divides  the  healthy  from  the  diseased 
tissue  with  a  more  or  less  wide  pale  area.  Miller  offers 
an  explanation  based  upon  an  optical  foundation  which 
assumes  that  the  dentin  in  this  region  has  become  homo- 
geneous. It  usually  appears  opaque  because  it  is  com- 
posed of  elements  of  different  refraction  coefficients 
(Tomes'  fibers,  sheaths  of  Xeumann,  ground-substance  and 
fibrils  of  the  ground-substance  which  excrete  lime).  The 
ground-substance  becomes  poorer  in  lime,  or,  on  the  other 
hand,  the  organic  become  richer  in  lime.  Thus  all  the 
constituents  of  the  dentin  possess  nearly  similar  refraction 
coefficients  which  might  explain  this  diaphanous  condi- 
tion. Chemical  analysis  has  demonstrated  that  the  cal- 
cium content  in  this  zone  is  in  fact  increased,  and  therefore 
transparency  results.  The  existence  of  this  phenomenon 
is  believed  by  Walkhoff  to  be  due  to  spreading  sclerosis, 
which  consists  of  a  contraction  of  the  dentinal  fibers,  and 
at  the  same  time  a  narrowing  of  the  lumen  of  the  denti- 
nal tubules.  This  explanation,  with  which  Miller  agrees, 
is  undoubtedly  the  best.  For,  as  a  fact,  the  diameters  of  the 
tubules  are  decidedly  decreased  in  the  transparent  zone. 

It  must  be  assumed  that  vital  processes  are  concerned 
in  this  connection  ;  perhaps  in  the  form  of  a  protective 
action  on  the  part  of  the  pulp  against  the  penetrating  bac- 
teria. However,  we  may  assume  that  the  process  is  vital, 
for  Miller  at  no  time  saw  the  transparent  zone  in  dead 
teeth.  We  have  stained  with  carbol-fuchsin  living  as 
well  as  dead  carious  teeth  and  present  on  Plate  22  the 
picture  of  a  living  tooth  in  which  the  transparent  zone 
remained  absolutely  unstained,  and  shows  a  sharp  contrast 
between  it  and  the  highly  red-stained  carious  dentin.  In 
a  dead  tooth,  however  (Plate  23),  the  red- stain  passing 
through  the  variousgrades  of  yellow  coloration,  and  becom- 
ing paler  and  paler,  gradually  fides  into  the  normal  den- 
tin. Plate  22  gives  the  distinct  impression  that  the  living 
tooth  resists  the  progress  of  the  caries,  while  Plate  23 
shows  the  tooth  to  be  absolutely  passive. 

The  zone  of  opacity,  contrary  to  the  foregoing  trans- 
parent  zone,  is   colored   a   deep  red   by  carbol  fuchsin 


216      DEFECTS  OF  HARD  TOOTH  SUBSTANCES. 

Plate  22. 

Carious  molar  tooth  whose  pulp  is  alive. 

a,  zone  of  transparency  ;  b,  zone  of  opacity ;  c,  zone  of  softening  ;  d, 
zone  of  disintegration.  Longitudinal  section.  Picric  acid.  Carbolfuclisin. 

Plate  23. 

Carious  molar  tooth  whose  pulp  is  dead. 

Longitudinal  section.     Picric  acid.    Carbolfuchsin. 

(Plate  22  6)  ;  a  proof  that  marked  changes  have  occurred 
in  this  region.  Some  of  the  dentinal  tubules  have  already 
been  penetrated  by  bacteria,  and  some  are  filled  with  other 
elements  of  a  flaky  or  spherical  form  between  which  hya- 
line tubules,  or  tubules  with  deposits  of  lime  may  be 
recognized.  The  extreme  opacity  of  this  layer  may  be 
explained  by  the  differences  in  the  contents  of  the  dentinal 
tubules.  By  gradual  changes  the  zone  of  opacity  passes 
into  the  zone  of  softening. 

This  is  the  layer  in  which  both  the  dentinal  tubules 
and  their  superficial  branches  are  filled  with  micro- 
organisms. Their  lumina  are  very  nearly  equally  dilated, 
and  the  sheaths  of  Neumann  are  swollen.  Because  of 
the  uniformity  of  its  structure,  this  zone  is  slightly 
transparent.     (Plate  22  c.) 

The  masses  of  fungi  which  are  originally  enclosed  in 
the  dentinal  tubules  gradually  become  confluent  to  form 
masses  of  ever  increasing  size.  The  layer  lying  next  to 
the  surface  undergoes  thegreatest  amount  of  destruction; 
in  this  region  the  tissue  is  constantly  undergoing 
destructive  changes  Avith  the  formation  of  detritus  which 
leads  to  a  loss  of  tooth  substance  (Plate  22  d). 

The  treatment  of  caries  has  been  described  in  detail  on 
page  217. 

The  projjhylaxis  should  above  all  things  be  directed 
against  the  exciting  causes,  for  the  predisposing  influences 
are  less  accessible.  It  is  therefore  highly  important,  in 
the  first  place,  to  thoroughly  clean  the  oral  cavity,  and  if 
possible  to  disinfect  it.  This  is  best  done  by  brushing  the 
teeth  with  a  good  tooth-powder  twice  a  day,  upon  arising 
in   the   morning   and  just  before  retiring  at  night.     It 


7ab.22. 


7ab.2-3. 


TREATMENT  OF  DEFECTS  OF  THE  TEETH.     217 

suffices  after  meals  to  thoroughly  riuse  the  teeth  "oith  a 
mouth  wash.  The  teeth  should  uot  only  be  brushed  in 
the  horizontal  direction,  but  also  in  the  vertical,  for  the 
former  method  forces  the  foreign  material  between  the 
teeth.  Ordinary  prepared  ch^lk  is  a  very  valuable  prep- 
aration as  it  does  not  injure  the  teeth.  To  give  it  a 
jileasant  taste,  j)eppermint  may  be  added,  pnd  to  bestow 
upou  it  a  bactericidal  action,  an  antiseptic  is  added.  Of 
the  antiseptics  employed  in  the  past  none  has  been  abso- 
lutely satisfjictor^' ;  chinosol,  however,  seems  to  have  a 
retarding  influence  upon  the  carious  processes.  It  is  a 
deodorant  and  an  astringent,  which  latter  is  of  importance 
in  relaxed  gums.  A  good  prescription  for  such  a  prep- 
aration is  as  follow  : 


R     Calcar.  carbon,  praecip., 

liiii 

(100.0), 

Sapon.  medicat., 

3ii 

(5.0), 

Chinosoli, 

gr.  i 

(0.05), 

01.  mentli.  pip.. 

gttS.  XT, 

(1.00). 

M.  and  Sig.     For  cleansing  the  teeth. 

I  also  think  that  the  addition  of  a  5  per  cent,  concen- 
traticm  of  chinosol  to  the  mouth  wash  is  useful.  Follow- 
ing is  a  comparatively  cheap  prescription  for  this  prepa- 
ration : 

R     Aqua  dist.  5iii                    (;90.0), 

Chinosoli  ,^ii.ss                     (10.0), 

Ol.  nienth.  pip.  gtts.xv.            gtts  xv. 

M.  and  Sig.  Mouth-wash.  Add  5  drops  to  \  glass  water. 


TREATMENT  OF  DEFECTS  OF  THE  TEETH. 

It  is  impossible  for  the  reader  to  familiarize  himself 
with  the  technic  required  in  treating  defects  of  the  teeth 
from  a  description  of  it.  Although  a  knowledge  of  this 
technic  can  only  be  accpiired  by  practical  work,  yet  we 
cannot  afford  to  omit  a  discussion  of  this  highly  impor- 
tant subject.  In  order  to  present  only  information  which 
is  actually  useful,  the  literature  of  Professors  Sachs  and 
Miller  is  largely  drawn  upon. 


218      TREATMENT  OF  DEFECTS  OF  THE  TEETH. 


L  THE  TREATMENT  OF  TOOTH  DEFECTS  BY  FILING 
AND  THE  USE  OF  NITRATE  OF  SILVER. 

The  Filing  of  Teeth. — The  early  form  of  practice 
when  small  defects  developed  on  the  proximal  surfaces 
was  to  remove  them  with  a  separating-file.  That  is,  both 
teeth  were  filed,  but  not  down  to  the  edge  of  the  gums, 


^^ 


Fig.  97. — a,  front  teeth  with  interstitial  foci  of  caries ;  h,  the  same  teeth 
whose  proximal  surfaces  have  been  ground  down  and  the  foci  of  caries 
removed.  At  the  necks  of  the  teeth  are  seen  the  "  shoulders  "  of  enamel  which 
are  intended  to  prevent  the  teeth  from  drawing  together  in  the  future;  c, 
cross  sections  through  the  crowns  of  two  upper  middle  incisor  teeth,  which 
show  that  more  of  the  lingual  than  of  the  labial  surface  has  been  tiled  away. 

where  a  small  portion  of  the  enamel  was  allowed  to 
remain,  which  formed  the  so-called  "  shoulder."  The 
object  of  this  shoulder  was  to  prevent  the  two  teeth  from 
drawing  close  together  in  the  course  of  time.  Thus,  they 
stood  further  apart  than  before  this  treatment,  and  were 
therefore  more  readily  kept  clean.  In  order  to  facilitate 
the  cleansing  by  making  what  was  called  self-cleansing 
spaces,  more  of  the  tooth  structure  was  ground  away  on 
the  lingual  than  on  the  labial  side,  and  the  oblique  lateral 
surface  thus  formed  was  as  carefully  polished  as  possible. 

I  have  never  been  able  to  observe  tliis  operation  on  the 
molar  teeth,  but  I  have  seen  it  quite  frequently  on  the 
front  teeth  in  old  individuals.  In  these  teeth  it  seems  to 
have  given  the  most  favorable  results,  for  a  return  of  the 
carious  process  was  extremely  rare  even  after  many 
years. 

This  therapeutic  agency  ought  to  be  reintroduced  to-day, 
especially  in  polyclinical  work.^     It  cannot  be  generally 

[1  The  author's  sentiment,  as  here  expressed,  can  in  no  sense  be  subscribed 
to.  There  can  be  no  question  as  to  the  error  of  this  method  of  treating  dental 
caries.  The  ideal  practice  is,  as  far  as  possible,  to  reproduce  the  normal 
physiological  conditiou,  that  is,  to  so  extend  the  filling  as  to  renew  the  cnntnct 
poi'nt.  This  to  protect  the  approximal  space  from  the  impact  of  food,  contrary 
to  the  antiquated  practise  of  cutting  so-called  self-cleansing  spaces  which, 
outside  of  its  mutilation  of  the  tooth,  invited  its  accumulation. — Ed.] 


TREATMENT  OF  TOOTH  DEFECTS.  219 

resorted  to,  however,  for  many  patients  object  to  sepa- 
ration of  their  front  teeth  because  it  destroys  their  beauty. 
Fig.  97  shows  the  manner  in  which  the  front  teeth  are 
filed. 

The  Silver-nitrate  Treatment. — Beginning  caries, 
as  well  as  wedge-shaped  defects,  are  favorably  influenced 
by  touching  the  affected  area  with  argentic  nitrate.  The 
surrounding  tissue  must  first  be  covered  with  a  varnish 
in  order  to  prevent  it  from  being  acted  upon  by  the 
caustic.  With  a  little  care  and  practice  this  measure 
may  be  accomplished  with  no  ill  results.  Stebbins,  with 
whom  Chupein  and  Szabo  agree,  recommends  the  silver- 
nitrate  treatment  even  for  larger  defects,  especially  in  the 
deciduous  teeth.  The  method  of  application  is  very 
simple,  and  consists  in  placing,  for  two  minutes,  a  piece 
of  silver  nitrate,  the  size  of  a  pin's  head,  into  the  moist 
cavities  from  which  all  the  softened  masses  have  been 
removed. 

The  favorable  action  of  argentic  nitrate  upon  the  course 
of  caries  may  be  explained,  by  the  insoluble  combinations 
which  it  forms  with  organic  tooth  substance,  and  thus 
withdrawing  the  nourishment  from  the  bacteria.  We 
may  assume  that  the  chemical  process  consists  in  the 
coagulation  of  the  albumin  and  the  formation  of  the 
albuminate  of  silver  oxid.  Furthermore,  since  the 
animal  tissues  always  contain  sodium  chlorid,  a  chemi- 
cal change  occurs  in  which  the  nitric  acid  of  the  argentic 
nitrate  combines  with  the  sodium,  and  the  chlorin  com- 
bines with  the  silver,  to  form  the  insoluble  chlorid  of 
silver.     Ag  FO,  +  Xa  CI  ---  Ag  CI  +  Na  NO,. 

The  spots  which  follow  the  ap])lication  of  this  prepar- 
ation turn  black  under  the  influence  of  daylight,  on 
account  of  which  the  argentic  nitrate  treatment  should 
not  be  employed  on  visible  tooth  surfaces. 

Since  the  cauterized  areas  are  worn  away  with  time,  the 
disease  process  may  later  begin  anew.  On  account  of 
the  foregoing  described  insoluble  combinations  which  it 
forms,  silver  nitrate  penetrates  but  to  a  very  slight  depth. 
If  a  prolonged  action  is  desired  the  diseased  focus  should 


220        TREATMENT  OF  DEFECTS  OF  THE  TEETH. 

be  cauterized  at  regular  intervals,  for  example,  every  six 
months. 

n.  THE  FILLING  OF  TEETH. 

The  previously  described  methods  are  likely  to  prevent 
further  extension  of  the  caries,  but  in  the  application  of 
the  file  a  large  amount  of  substance  must  be  sacrificed 
while  the  argentic  nitrate  treatment  must  be  continually 
repeated.  The  ideal  method  therefore  consists  in  a 
restoration  of  the  normal  conditions  as  true  to  nature  as 
possible.  This  is  accomplished  in  the  teeth  in  an  almost 
perfect  manner,  by  filling  the  defects  which  have 
developed.  The  results  of  this  plastic  operation  depend 
npon  the  selection  of  the  filling  material  and  especially 
npon  the  ability  of  the  operator. 

FILLING  MATERIALS. 

As  far  as  possible  a  filling  material  should  possess  the 
following  properties. 

It  must  be  of  such  a  consistency  that  it  is  flexible,  or 
able  to  be  kneaded,  in  order  that  it  may  be  readily 
adapted  to  the  walls  of  the  cavity. 

It  must  be  able  to  withstand  the  influence  of  the  oral 
fluids. 

In  areas  wdiere  it  is  exposed  to  mechanical  influences 
it  must  be  hard  as  possible. 

It  is  desirable,  especially  in  sensitive  teeth,  that  the 
material  be  a  poor  conductor  of  heat. 

It  should  have  a  tooth-like  color;  this,  however,  needs 
to  be  considered  only  in  the  visible  regions.  For  the 
exact  regions  indicated  compare  Arkovy,  "  Indications.  " 

The  most  important  requisites  are  numbers  2  and  3, 
which  may  be  expressed  by  one  term,  indestructibility. 
Under  no  circumstances  should  a  material  be  employed 
for  a  permanent  filling  which  lacks  these  properties. 

We  will  next  study  the  materials  which  are  used  for 
filling  teeth.  They  are  gold,  a  union  of  tin  and  gold, 
amalgam,  cement  (zinc  phosphate),  combination  of  amal- 
gam and  cement,  etc.,  enamel  and  guttapercha. 


THE  FILLING   OF  TEETH.  221 

Gold. — Gold  fulfils  the  most  important  requirements 
in  an  eminently  satisfactory  manner,  for  it  is  capable  of 
great  resistance  to  mechanical  and  chemical  iutiueuces. 
It  is  only  in  regard  to  its  conductivity  and  its  shiny 
yellow  color  that  it  fails  to  fulfil  the  requirements  of  an 
ideal  filling  material.  Gold  in  the  form  of  foils,  as 
placed  upon  the  market,  are  usually  numbered,  expressing 
the  weight  of  the  individual  sheets  and  also  the  thickness 
of  the  foils  when  they  are  of  equal  size.  For  example,  if 
foil  No.  5  weighs  five  grammes  and  a  like-sized  foil  No. 
30,  thirty  grammes,  thickness  of  No.  30  is  greater  than 
that  of  No.  5. 

Before  using,  the  foil  is  cut  into  strips  and  repeatedly 
folded  or  rolled.  The  gold  cylinders,  however,  which  can 
be  bought,  are  much  more  convenient  and  more  satisfac- 
tory than  the  self-rolled  foils.  The  gold  cylinders  may 
be  obtained  in  any  desirable  size. 

Another  form  is  the  crystal  gold,  which  is  crystallized 
from  a  gold  solution. 

More  important  than  these  outer  forms  of  gold  is  a 
physical  difference,  namely  that  one  preparation  is  cohesive 
and  another  noncohesive.  As  is  indicated  by  the  term, 
the  cohesive  forms  of  gold  have  the  property  of  adhering 
to  each  other,  while  the  noncohesive  are  unable  to  do  so. 
Moreover  the  first  is  harder  than  the  latter. 

Combinations  of  Tin  and  Gold. — Many  practition- 
ers prefer  to  use  in  place  of  the  pure  gold  a  combination 
of  chemically  pure  gold  and  tin.  This  tin-gold  is  claimed 
to  have  many  advantages  over  pure  gold.  It  is  less  diffi- 
cult to  fill  a  tooth  with  this  pre))arati()n  ;  its  conductivity 
is  much  less  than  that  of  gold  ;  and  the  occurrence  of 
secondary  caries  is  practically  impossible,  even  in  cavities 
which  lie  deeply  under  the  surface  of  the  tooth-gum.  The 
only  disadvantage  is  the  dark  color  of  such  a  filling. 
When  the  ad vantao-es  and  disadvantages  are  weiohed,  the 
conclusion  will  be  reached  that  tin-gold  is  not  very  adapt- 
able for  complete  fillings,  but  we  must  not  deny  it  a  cer- 
tain value  as  a  foundation  for  central  and  especially 
approximal    fillings   which   extend   below  the  gum  line. 


222      TREATMENT  OF  DEFECTS  OF  THE  TEETH. 

This  preparation  is  made  by  laying  a  sheet  or  leaf  of  tin 
upon  one  of  gold  and  twisting  them  into  a  loose  cable. 
Since  the  tin  oxidizes  in  the  air,  a  large  supply  of  this 
filling  material  cannot  be  prepared. 

Amalgam. — The  amalgams  belong  to  the  so-called 
jAastic filling  material ;  that  is,  they  change  after  a  time  from 
the  soft,  dough-like  state  in  which  they  are  introduced  into 
the  cavity  into  a  hard  condition.  They  are  preferable  to 
gold,  because  they  are  poorer  thermal  conductors.  Their 
chief  disadvantages,  however,  consist  in  the  fact  that  many 
amalgams  later  undergo  a  change  of  shape,  that  they  are 
more  or  less  easily  subject  to  mechanical  and  chemical  dis- 
turbances, and  tliat  they  do  not  possess  a  color  which  is 
pleasing  to  the  eye.  Their  employment  is  limited  in  visible 
teeth  on  account  of  this  color,  which  many  preparations 
even  transmit  to  the  tooth  substances. 

The  amalgams  are  combinations  of  simple  metals 
(binary  amalgams),  or  of  alloys  (ternary,  quaternary,  etc.) 
with  mercury.  This  material  may  be  obtained  as  ready- 
prepared  amalgam  (copperamalgams),  or  the  metal  is  not 
amalgamated  until  just  before  its  use  in  the  operating  room. 
The  copper-amalgam  is  sold  in  small 
sheets  or  blocks,  which  are  so  strongly 
heated  before  being  employed  that 
minute  drops  of  mercury  exude.  They 
^  are  then  ground  in  a  small  mortar  and 
kneaded  between  the  fingers  until  a 
soft  mass  is  formed.  Amalgam  pre- 
pared in  this  manner  is  introduced 
in  inaccessible  cavities  with  diffi- 
culty, for  it  tends  to  cling  to  the  walls. 
Fig.  98.-0,  copper-amai-  Accordiup;   to    Miller,    copper-amal- 

gam;    b,  copper-amalgam  fc>  _  \        rl^ 

with  the  addition  of  3  per  rams  cxcrt  an  autiscptic  action  upon 

cent,  pure  tin  (tinfoil).  S        ,       ,i  i     ,  rni  •      • 

the  tootli  substances,  inis  is  more- 
over true  of  the  few  amalgams  which  do  not  contract,  and 
are,  therefore,  when  careful  work  is  done  in  all  other  res- 
pects, an  excellent  filling  material,  especially  for  the 
poorer  practice. 

It  is  to  be  regretted  that   in   many  patients   amalgam 


THE  FILLING   OF  TEETB.  223 

causes  considerable  discoloration  of  the  teeth,  and  can, 
therefore,  only  be  employed  in  the  posterior  teeth.  There 
is  still  one  other  disadvantage,  namely,  that  the  surface  of 
the  filling-  sooner  or  later  wears  oif.  An  amalgam  filling 
is  not  only  ground  down  by  mastication  and  brushing, 
but  its  surfaces,  especially  the  approximal,  are  discolored 
by  the  acids  of  the  mouth.  Professor  Miller,  however, 
offers  a  remedy  which  will  make  the  copper -amalgam 
resistive.  This  consists  in  the  addition  of  about  3  per 
cent,  pure  tin,  \yhich  must  be  thoroughly  incorporated  in 
the  form  of  a  piece  of  tin  foil  into  the  dough-like  mass. 
Unfortunately,  however,  this  causes  the  copper-amalgam 
to  lose  its  antiseptic  action.  It  is,  therefore,  better  to  coat 
the  walls  of  the  cavity  with  ordinary  (antiseptic)  copper- 
amalgam,  and  complete  the  filling  with  Miller's  composi- 
tion as  demonstrated  in  Fig.  98. 

Most  of  the  other  amalgams  are  chiefly  composed  of  tin 
and  silver,  to  which  are  added  a  small  percentage  of  zinc, 
copper,  gold,  platinum,  cadmium,  antimony,  etc. 

The  amalgams,  which  are  composed  of  more  or  less 
complicated  alloys,  unfortunately  have  the  tendency  during 
the  hardening  period,  or  even  later,  of  contracting. 
According  to  Dodge  this  phenomenon  is  due  to  the  ten- 
dency of  the  stiffened  mass  to  assume  a  sphericle  shape. 
Whether  this  is  really  true,  or  whether  other  factors  are 
concerned,  has  not  been  positively  decided.  On  the  con- 
trary, in  other  cases,  an  expansion  takes  place  which 
shows  itself  h\  the  rising  of  the  amalgam  above  the 
surface  of  the  cavity.  Indeed  this  expansion  may  break 
off  or  fracture  weak  walls  of  the  cavity. 

Cement  (^inc  Phosphate). — Commercial  dental 
cement  consists  of  a  powder  and  a  fluid  which  are  mixed 
and  kneaded  together  before  use.  The  powder  is  a  base 
and  the  fluid  an  acid.  The  powder  is  simply  zinc  oxid, 
to  which  usually  other  metallic  oxids,  as  well  as  silicic 
acid  and  coloring  matters,  are  added.  The  fluid  usually 
employed  is  orthophosphoric  acid,  which  is  placed  on  the 
market  in  a  thickly  liquid  form.  By  mixing  the  two  con- 
stituents a^  mass  is  formed  which  hardens  comparatively 


224     TREATMENT  OF  DEFECTS  OF  THE  TEETH. 

rapidly,  and  which  is  in  reality  nothing  else  than  zincpJios- 
■phate.  This  material  is  a  poor  conductor ;  it  is  the  only 
filling  which  adheres  to  the  walls  of  the  cavity,  and  pos- 
sesses an  unnoticeable  color  even  though  it  is  not  exactly  the 
color  of  a  tooth.  The  chief  disadvantage,  however,  which 
limits  its  employment  considerably,  is  its  tendency  to 
undergo  destruction  by  the  various  agents  in  the  mouth. 
A  good  cement  may  last  for  five  years  or  more  if 
the  conditions  of  the  mouth  are  favorable,  yet  this  is  an 
exception  which  is  by  no  means  the  rule.  On  the  con- 
trary, daily  observations  show  that  the  cement  in  many 
mouths  may  be  completely  dissolved  even  in  one  year's 
time. 

Cement  does  good  service  in  sensitive,  poor,  or  vain 
patients,  whose  front  teeth  cannot  be  filled  with  gold. 
There  is  no  urgent  indication  for  the  employment  of  this 
material  in  the  molars.  It  must  be  borne  in  mind, 
furthermore,  that  this  material  is  but  a  provisional  pre- 
server of  teeth.  On  the  other  hand  the  cements  are  par- 
ticularly well  suited  for  fastening  crowns,  bridges  and 
porcelain  fillings. 

Mixtures  of  Amalgam,  and  Cement. — It  is  recom- 
mended in  order  to  prevent  rapid  destruction  of  the  ce- 
ment, that  it  be  mixed  with  metal  filings.  ]\Iore  useful 
than  this,  however,  is  freshly  kneaded  amalgam  to  which 
one-sixth  as  much  cement  has  been  added.  Such  a  filling 
is  less  suitable  in  color,  but  is  more  resistive  at  the  chew- 
ing surface,  as  well  as  at  the  border  of  the  gums,  than 
are  the  simple  cement  fillings. 

l^namel  or  Porcelain. — Enamel,  glass  and  porce- 
lain fillings  are  employed  for  concealing  defects  in  visible 
areas.  For  this  purpose  a  mass  of  glass  or  porcelain  is 
ground  into  a  powder  and  then  melted  in  a  castor  matrix 
of  gold  or  platinum  foil,  Avhich  has  been  taken  of  the  cavity 
to  be  filled.  The  small  piece  of  enamel  thus  obtained  is 
then  fastened  into  place  with  cement.  The  appearance  of 
such  a  filling  is  very  pleasing,  and  its  hardness,  power  of 
resistance,  and  conductive  properties  leave  nothing  to  be 
desired.      Inasmuch  as  these  fillings  are  fastened  with 


THE  TECHNIC  OF  FILLING   OF  TEETH.         225 

zinc  phosphate,  they  also  have  in  a  measure  the  disadvan- 
tages of  cement. 

Guttapercha. — The  guttapercha  employed  in  den- 
tistry is  a  preparation  which  is  obtained  by  mixing  gutta- 
percha, softened  through  heat,  Mith  from  four  to  seven 
parts  of  zinc  oxid.  It  is  useful  in  those  locations  in 
which  it  is  not  likely  to  be  worn  away,  elsewhere  it  can 
only  be  regarded  as  a  temporary  filling  material. 

It  is  of  especial  value  because  of  its  poor  conductive 
properties,  and  as  a  base  for  metallic  fillings;  and  because 
of  its  resistance  to  chemical  influences,  it  is  employed 
with  advantage  in  defects  which  reach  below  the  gum. 
Many  dentists  prefer  to  fill  the  root  canals  with  gutta- 
percha, and  also  to  fasten  crowns  and  bridges  with  it. 

THE  TECHNIC  OF  FILLING  OF  TEETH, 
EXAMINATION  OF  THE  TEETH. 

It  is  not  an  easy  matter  for  the  beginner  to  examine  the 
teeth  for  carious  areas.  All  of  the  defects  are  not  visible, 
and  many  are  often  concealed,  as  for  instance,  on  a  prox- 
imal surface.  Small  defects  of  the  enamel  are  also  over- 
looked which  often  widen  into  a  larger  cavity  in  the 
interior  of  the  tooth.  This  mistake  is  likely  to  lead  to 
serious  results,  and  therefore  the  examination  of  the  teeth 
must  be  systemically  undertaken.  One  should  always 
begin  the  examination  with  the  upper  molars  of  one  side, 
usually  the  left,  and  gradually  work  along  to  the  bicuspids, 
the  cuspid  and  the  incisor  teeth.  Then  examine  in  the 
same  order  of  rotation  the  lower  jaw  of  the  same  side, 
and  then  pass  over  to  the  other  side  of  the  mouth,  observing 
the  same  order  there.  By  conducting  the  examination  in 
this  manner  the  danger  of  overlooking  a  diseased  condi- 
tion is  avoided. 

The  instruments  required  for  examination  are  an  oral 
mirror  and  an  explorer.  The  latter  is  illustrated  in  Fig. 
99.  The  mirror  which  is  employed  to  illuminate  the 
teeth  is  held  in  the  left  hand  and  the  instrument  in  the 
right.  The  explorer  must  have  a  sharp  and  delicate 
15 


226 


THE  TECHNIC  OF  FILLING   OF  TEETB. 


point  in  order  to  detect  minute  cavities.  It  is  impossible 
to  locate  some  carious  defects  witli  an  instrument,  as  is 
the  case  for  instance  in  beginning  superficial  caries,  in 
which  a  loss  of  substance  has  not  as  yet  occurred.     This 


Fig.  99.— Instru- 
ment for  explor- 
ing carious  teeth. 


Fig.  100.— Sepa- 
rating file. 


Fig.  101.— Polishing 
disk  for  the  dental 
engine. 


defect,  however,  may  be  detected  by  the  color,  which  is 
either  opaque  or  dark.  The  same  holds  true  of  cavities 
on  the  proximal  surfaces,  which  are  easily  overlooked 
when  the  teeth  press  tightly  upon  each  other ;  consider- 
able assistance  is  obtained  in  such  cases  by  separating  the 
teeth  either  with  India-rubber  or  a  cotton  wedge. 


SEPARATING  THE  TEETH. 
It  is  absolutely  necessary  to  force  apart  such  teeth  as 
have  defects  in  their  approximal  surfaces,  for  it  is  highly 
important  in  the  filling  of  teeth  that  a  good  view  of  the 
field  of  operation  be  obtained,  and  that  it  be  accessible  to 
the  instruments. 


SEPARATING   THE  TEETH.  227 

The  older  method  of  separating  the  molars,  and  it  is 
practiced  by  some  operators  to-dav,  is  to  use  the  sej^ara- 
ting-file  (Fig.  100)  or  disc  (Fig.  101).  In  the  case  of  the 
bicuspids,  and  especially  the  front  teeth,  it  suffices  to  pack 
the  space  between  the  teeth  with  absorbent  cotton  for 
several  days.  The  cotton  becomes  swollen  from  the  ab- 
sorption of  moisture,  and  gradually  causes  the  teeth  to.be 
forced  apart  without  much  inconvenience.  Cotton  is  of 
little  use  if  the  teeth  are  located  in  an  unyielding  portion 
of  the  alveolar  process,  as  in  old  people.  In  that  case  a 
piece  of  India-rubber,  in  the  form  it  is  sold  to  the  trade, 
gives  better  and  more  satisfactory  results.  At  least  rubber 
may  be  used  for  the  first  day  and  then  replaced  by  cotton. 
Too  large  a  piece  of  rubber,  however,  must  not  be  employed, 


Fig.  102.— Elliott's  separator. 


for  the  pressure  it  causes  might  result  in  a  periostitis. 
These  separating  materials  must  remain  in  place  for  at 
least  two  days.  If  it  is  intended  to  introduce  a  gold 
filling,  which  causes  considerable  strain  upon  the  tooth, 
the  operation  should  not  be  performed  immediately  after 
the  separation,  for  at  that  time  the  periodontium  is  irri- 
tated and  highly  sensitive.  Instead  of  filling  the  tooth 
immediately  after  separation,  it  is  better  to  insert  a 
small  piece  of  guttapercha  for  several  days  in  order  (tempo- 
rarily) to  fix  the  teeth.  After  tin's  has  been  done  the  tooth 
is  better  able  to  resist  the  malleting  incident  to  a  gold 
filling  without  ill  eifects.  If  there  is  need  for  hurry,  the 
teeth  may  be  separated  immediately  with  a  wedge-shaped 


228 


THE  TECHNIC  OF  FILLING   OF  TEETH. 


piece  of  wood  which  is  pressed  between  the  teeth.  The 
same  effect  may  be  obtained  from  a  so-called  mechan- 
ical separator.        Such   an  instrument  consists   of    two 


Fig. 


103.— Keeping  the  operative  field  dry  by  means  of  absorbent  sub- 
stances :  in  this  case  a  napkin  is  used. 


metallic  cones  which  are  forced  from  both  sides  between 
the  teeth.  The  most  useful  of  the  steel  separators  is  the 
one  devised  by  Elliott,  which  is  illustrated  in  Fig.  102. 


DRYING  THE  CAVITIES.  229 

DRYING  THE  CAVITIES. 

For  operations  which  are  of  short  duration,  it  is  suffi- 
cient to  keep  the  region  dry  by  means  of  a  small  napkin, 
absorbent  cotton,  etc.,  in  the  manner  shown  in  Fig.  103, 
The  absorbent  substance  is  placed,  in  the  upper  jaw, 
between  the  cheek  or  lips  and  the  alveolar  process  ;  in  the 
lower  jaw,  it  is  applied  in  the  same  region,  but  it  is  also 
necessary  to  keep  the  floor  of  the  mouth  dry  because  of 
the  openings  of  the  excretory  ducts  of  the  salivary  glands 
which  are  situated  there. 

If  the  field  of  operation  is  to  be  kept  dry  for  a  greater 
length  of  time,  the  rubber  dam  {cofferdam)  introduced  by 
S.  C.  Barnum  should  be  employed. 

The  simplest  manner  of  applying  the  cofPerdam  on  the 
front  teeth  consists,  first,  in  perforating  it  with  a  punch  a 
number  of  times  equal  to  the  number  of  teeth  which  it  is 
desirous  to  keep  dry  (Fig.  104).  The  rubber  is  then 
drawn  over  the  teeth  in  such  a  manner  that  they  pass 
through  these  perforations.  Their  isolation  may  be  made 
more  complete  by  tying  a  thread  or  waxed  silk  around  the 
neck  of  each  tooth.  In  order  to  spread  the  rubber  sheet 
out  smoothly,  a  holder  is  employed,  which  consists  of  two 
clamps  joined  to  each  other  by  a  band. 


Fig.  lOJ.— Punch  for  the  cofferdam. 


By  hooking  these  clamps  to  the  sides  of  the  rubber 
and  by  placing  the  strap  around  the  head,  lateral  tension 
is  brought  to  bear  upon  the  coflFerdam  (Fig.  105).  A 
small  weight  may  be  attached  at  its  lower  edge.  When 
operating  upon  approximal  surfaces  we  must  not  neglect, 


230         THE  TECHNiC  OF  FILLING   OF  TEETH. 

PLATE  24. 
Application  of  the  rubber  dam  and  other  appliances  of  assistance 
in  deep  caries  of  the  front  teeth. — This  illustration  shows  us  a  not  very- 
infrequent  condition,  in  which  a  front  incisor  tooth  is  so  badly  destroyed 
on  both  sides  by  a  deep  carious  process,  that  one  is  tempted  to  remove  the 
remainder  of  the  crown,  and  to  apply  a  porcelain  crown.  If,  however, 
for  any  reason,  it  is  desirous  to  preserve  and  fill  the  tooth,  extreme  care 
must  be  observed  on  account  of  the  possibility  of  fracturing  a  portion  of 
this  weakened  crown.  For  the  purpose  of  securing  a  dry  operative  field 
proceed  exactly  as  in  less  atfected  teeth.  In  this  case  the  cofferdam  has 
three  holes  punched  into  it,  through  which  the  diseased  tooth  as  well  as 
the  two  adjoining  teeth  have  been  inserted.  Two  weights  draw  the  dam 
downward  and  two  clamps,  which  are  joined  by  a  band  passing  around 
the  head,  spread  it  laterally.  A  German  silver  band  (according  to 
Herbst)  acts  as  a  matrix,  and  is  applied  to  the  diseased  tooth  in  such  a 
manner,  as  shown  in  the  illustration,  that  it  takes  the  place  of  the 
portion  of  the  posterior  wall  of  the  tooth  which  has  been  destroyed. 
This  matrix  is  best  fixed  by  applying  some  heated  Stent's  material  back 
of  the  tooth-row  and  then  allowing  the  month  to  close. 

in  spite  of  the  above  precautions,  to  insert  a  wooden 
wedge  between  the  teeth,  a  particularly  difficult  case  is 
illustrated  in  Plate  24,  to  which,  with  its  accompanying 
text,  the  reader  is  referred. 

Ligatures  are  easily  applied  to  the  front  teeth  and  act 
very  satisfactorily.  Clamps  are  preferred  for  the  back 
teeth.  They  not  only  cling  more  tightly  to  the  neck  of 
the  tooth,  but  their  lateral  pieces  also  press  the  rubber 
sheet  downward,  which  is  an  advantage  not  to  be  de- 
preciated, considering  the  poor  light  and  the  lack  of  room 
in  which  one  is  often  compelled  to  operate.  Such  a  clamp 
for  the  molar  teeth  is  shown  in  Fig.  106.  As  especially 
constructed  clamps  are  required  for  abnormally  built  teeth, 
it  is  necessary  to  discuss  this  subject  in  greater  detail. 
A  clamp  which  gives  excellent  service  in  the  filling  of 
defects  extending  high  up  in  the  neighborhood  of  the 
neck  of  the  tooth  is  the  one  devised  by  Hatch  (Fig.  107). 
By  means  of  it  the  gum  may  be  pushed  upward  without 
causing  any  or  but  little  pain;  and  is  of  further  advantage, 
because  it  is  so  constructed  that  it  is  never  in  the  way 
during  the  operation. 

In  applying  the  rubber  dam  it  is  more  practical  to 
first  pass  the  side-pieces  of  the  clamp  through  the  opening 
in  the  rubber  outside  of  the  mouth,  and  then  applying  the 
clamp  as  if  the  cofferdam  were  not  attached. 


Tab.  24.. 


PREPARATION  OF  CAVITIES. 


231 


This  is  then  followed  by  simply  stretching  the  India- 
rubber  over  the  lateral  horizontal  portions  of  the  clamp. 
Fig,  109  shows  the  manner  of  applying  the  clamp,  with 
the  rubber  wrapped  about  the  handles  of  the  forceps. 

The  coflPerdam  is  not  only  of  value  in  keeping  the  field 
of  operation  dry,  but  serves  also  to  protect  the  mucous 


Fig.  105.— The  correct  application  of  the  cofferdam  to  the  front  teeth. 

membrane  against  toxic  or  irritating  medications,  as  well 
as  injuries  from  polishing  disks,  etc. 

PREPARATION  OF  CAVITIES. 

Before  discussing  the  various  methods  of  preparing 
cavities,  it  will  be  best  to  first  refer  to  the  folloMing 
general  considerations. 


232 


THE  TEGHNIG  OF  FILLING   OF  TEETH. 


It  is  important  in  the  first  place  to  obtain  a  good  view 
of  the  cavity.  It  is  to  be  regretted  that  many  practitioners 
pay  little  regard  to  this  fundamental  law  and  instead  pass 
their  drills  into  the  depths  of  cavities,  the  interior  of 


Fig.  106.— a  lower  molar  to  -which 
the  cofferdam  is  fixed  by  means  of 
a  clamp.  A  silk  thread  (a)  is  drawn 
between  the  isolated  tooth  and  its 
neighbor. 


Fig.  107.— The  clamp  of  Hatch  for 
cervical  cavities,  in  position.  The 
cofferdam,  is  not  sho^^•n. 


which  are  completely  hidden.  The  amount  of  damage 
that  such  a  procedure  may  cause  can  be  easily  understood. 
The  previously  described  separation  of  the  teeth  serves  to 
bring  the  approximal  defects  into   view,  but  in  every 


Fig.  108.— Clamp-forceps. 


variety  of  cavity  it  may  happen,  in  spite  of  the  fact  that 
the  superficial  portion  of  the  defect  is  plainly  seen,  that  a 
false  idea  is  obtained  as  to  the  depth  of  the  decay.  As 
we  know,  enamel  is  poorer  in  organic  matter  than  the 


PREPARATION  OF  CAVITIES. 


233 


dentin.  Therefore  caries  spreads  more  rapidly  in  the 
dentin  than  in  the  enamel,  and  the  latter  extending  over 
the  cavity  forms  a  covering  or  roof  to  it. 


Fig.  109.— The  most  convenient  method  of  applying  the  rubber  sheet  (with 
fixation  of  the  clamp). 

Our  first  object  is  to  remove  these  overhanging  enamel 
walls.  This  may  be  accomplished  by  means  of  a  small 
bur  or  drill ;  the  best  for  this  purpose  is  the  fissure  bur, 
or  what  is  known  as  a  plug  finishing  bur.  If  the  edges 
are  not  too  strong,  they  may  be  removed  with  the  enamel- 
chisel,  which  is  useful  in  very  many  cases.  But  the 
enamel  edges  must  nowhere  extend  over  the  dentin,  for 


Fig.  110.— Enamel-chisel. 

they  may  easily  become  fractured  in  the  future.  They 
must  also  form  a  right  angle  as  nearly  as  possible  to  the 
tooth  surface.  This  also  holds  true  for  the  whole  border 
of  the  cavity,  including  both  the  enamel  and  the  dentin. 
If  in  a  cavity  too  much  of  the  structure  underneath  the 
overhanging  edges  has  been  destroyed,  as  shown  in  Fig. 
Ill  a,  the  weakened  borders  tend  subsequently  to  break 


234 


THE  TECHNIG  OF  FILLING   OF  TEETH. 


off.  If,  however,  the  enamel  walls  are  cut  down  in  tne 
shape  of  a  funnel  (  Fig.  Ill,  6  )  the  filling  material  would 
form  a  shallow  and  weak  layer. 


Fig.  111.— a,  undermined  borders  of  a  cavity  (tooth-edges  too  weak) ;  b, 
funnel-shaped  borders  of  a  cavity  (borders  too  weak  for  the  filling  material) ; 
c,  cavity  with  nearly  perpendicular  edges  (correct). 

Since  thin  tooth  walls  and  thin  walls  of  filling  material 
are  easily  fractured,  the  only  correctly  shaped  borders  are, 
therefore,  those  Mdiich  form  almost  a  right  angle  with  the 
cavity,  as  is  demonstrated  in  Fig.  Ill  c. 


a  h 

Fig.  112.— a,  narrow  cavity  ;  6,  the  same  cavity  artificially  enlarged. 

It  is  much  more  agreeable  to  the  patient  and  more 
rapid  of  execution  to  remove  the  softened  dentin  with  an 


Fig.  113.— Spoon-excavator. 

excavator  instead  of  a  drill.     For  this  purpose  the  spoon- 
excavator  pictured  in  Fig.  113  is  especially  useful.     It 


PREPARATION  OF  CAVITIES. 


235 


can  be  obtained  in  all  sizes.  The  excavator  must  of 
course  be  as  sharp  as  a  razor.  The  bur  should  not  be 
employed  in  operating  upon  the  cavity  until  the  softened 
mass  of  dentin  has  been  removed.  The  most  useful 
forms  of  burs  are  shown  in  Fig.  114.     As  motive  power 


Fig.  114.— Burs  for  the  dental  engine :    a,  round  bur ;   b,  wheel  bur ;  c, 
inverted  cone  bur;    (/,  lissuie  bur. 

the  treadle  dental  engine  is  usually  employed,  but  the 
electric  engine  acts  much  more  uniformly,  and  permits 
the  hand  which  guides  the  drill  to  be  much  steadier 
because  the  body  is  not  shaken  by  the  treading  of  the 
foot-power  a])paratus. 


Fig.  115. — Air  syringe  for  drying  cavities. 

Before  inserting  the  filling,  the  cavity  must  be  absohdeJy 
dry.  If  the  tooth  be  protected  by  a  cofferdam,  so  that 
even  the  vapor  is  guarded  against,  the  cavity  may  be 
considered  dry,  and  it  is  then  only  necessary  to  remove 
the  dust  which  has  collected,  by  means  of  the  syringe 
shown  in  Fig.  115.  The  cavity  must  furthermore  be 
thoroughly  dried.     This  is  accomplished  by  the  use  of 


236         THE  TECHNIC  OF  FILLING   OF  TEETH. 

little  pledgets  of  cotton  and  moderate  blasts  of  hot  air  from 
the  chip  blower  or  air  syringe.  The  simple  air  syringe 
illustrated  in  Fig.  115,  the  point  of  which  is  held  before 
using  in  a  bright  flame,  gives  better  service  than  the  hot 
air  spray  which  is  heated  by  electricity. 

We  frequently  read  that  the  cavity  should  be  sterilized 
before  introducing  the  filling.  If,  however,  practitioners 
were  questioned  in  regard  to  this  point,  we  would  find 
very  few  who  live  up  to  this  law.  The  drilling  away  of 
the  infected  portions  of  a  tooth  already  sterilizes  the 
cavity  in  a  mechanical  way.  If  we  were  to  carry  out 
this  rule  to  the  letter,  it  would  be  necessary,  since  few 
micro-organisms  always  penetrate  deeply  into  the  dentinal 
canals,  to  excavate  deep  into  the  tooth  structure  which 
would  be  dangerous  to  the  pulp.  The  chemical  steriliza- 
tion, as  it  is  occasionally  performed,  consists  in  washing 
the  cavity  with  an  antiseptic,  or  in  allowing  it  to  remain 
there  for  a  few  moments.  This  is  correct  in  principle, 
but  it  must  not  be  forgotten  that  the  short  duration  during 
which  the  antiseptic  acts  affects  or  destroys  only  the 
superficial  vegetative  bacteria.  No  doubt  the  most  reli- 
able antiseptic  is  formaldehyde  of  which  a  10  per  cent,  to 
40  per  cent,  solution  of  the  commercial  form  may  be 
applied  to  the  cavity  for  a  few  minutes,  the  resulting  pain 
being  of  no  consequence.  Chlorphenol  is  also  of  value 
and  its  employment  causes  no  pain.  The  longer  the 
antiseptic  is  allowed  to  act  the  more  effective  it  becomes. 
As  a  rule,  the  hermetically  sealing  of  a  cavity  by  a  filling 
seems  to  exert  an  unfavorable  influence  upou  the  bacteria 
of  caries,  for  the  process  progresses  very  slowly  even  when 
carious  dentin  has  been  allowed  to  remain.  The  exclusion 
of  air  is  hardly  worthy  of  consideration,  for  many  of  these 
organisms  are  anserobic  or  facultative  anaerobic.  It  is 
more  essential,  in  closing  the  cavity,  that  no  nutritive 
material  can  reach  the  bacteria,  for  thus  they  are  com- 
pelled to  depend  exclusively  upon  the  sparse  albumin  of 
the  tooth  substances,  which  accounts  for  the  slow  pro- 
gression of  the  carious  process. 


LOCALIZATION  OF  THE  TEETH. 


237 


LOCALIZATION  OF  THE  TEETH. 

Before  considering  more  closely  the  application  of  the 
individual  materials,  we  must  understand  the  areas  of 
predilection  of  the  caries. 


Fig.  116.— Localization  of  caries  :  a,  central ;  b,  approximal ;  c,  labial  ;  d,  cer- 
vical ;  €,  subcervical. 

If  the  defect  occur  on  the  masticating  surface  (Fig. 
116  «)  ;it  is  called  central,  if  on  the  opposing  surfaces  of 
two  teeth,  approximal  (Fig.  116  6) ;  if  on  the  labial  sur- 
face, it  is  termed  labial  (Fig.  116  e) ;  if  at  the  neck  of 


<L  b  Q 

Fig.  117.— a,  caries  superficialis ;  b,  caries  media ;  c,  caries  profunda. 

the  tooth,  cervical  (Fig,  116  d) ;  and  when  reaching  deeper 
than  the  neck  of  the  tooth  it  is  designated  subcervical 
(Fig.  116  e).  Of  these  various  types  all  combinations 
occur,  such  as  approximal-central,  etc. 

With  reference   to   the   depth    to   which   the   process 
extends,  we  speak  of  caries  supcrjicialis  when  only  the 


238         THE  TECHNIC  OF  FILLING   OF  TEETH. 

enamel  is  involved  and  the  dentin  is  not  reached.  In 
caries  media  not  only  the  enamel  but  also  the  dentin,  even 
though  but  slightly,  are  diseased.  We  speak  of  caries 
profimda  when  the  carious  process  has  extended  to  the 
neighborhood  of  the  pulp  or  when  the  latter  has  been 
exposed  in  any  region,  or  infected  from  the  caries.  These 
conditions  are  illustrated  in  Fig.  117  a,  b,  and  c. 

MATRICES. 

Inasmuch  as  we  recognize  central  cavities,  those  having 
all  the  walls,  as  the  easiest  to  fill,  it  is  good  practice  to 
attempt  to  convert  all  cavities  into  that  form  of  cavity. 
This  is  accomplished  through  a  small  appliance  called 
the  matrix.  In  order  to  supply,  in  approximal-central 
cavities,  the  approximal  wall,  it  has  been  the  custom  for 
along  time  to  simply  press  a  small  piece  of  metal  (German 
silver  or  steel)  between  the  two  teeth,  and  between  this 
strip  of  metal  and  the  healthy  tooth  a  metallic  peg,  a 
wooden  cone,  or  a  little  guttapercha  is  inserted,  in  order 
to  make  the  wall  more  secure  (Fig.  118  c). 


WW 


a,  " 

Fig.  118.—  a,  kohinoor-celluloid  matrix  ;  6,  matrix  of  MiUer ;  c,  metallic  strip 
and  wooden  cone. 

Such  German  silver  or  steel  strips  are  easily  made  and 
for  ordinary  cases  are  preferable  to  most  of  the  matrices 
found  upon  the  market.  The  filling  however  assumes  on 
account  of  it,  a  flat,  and  not  the  true  shape  of  the  tooth. 
This  disadvantage  is  overcome  by  the  matrix  devised^  by 
Jach,  which  is  slightly  curved  outward.  To  be  effective, 
this  instrument  must  be  tightly  fastened  into  place.  This 
requirement  is  satisfactorily  fulfilled  by  the  ring  matrix  of 


MATRICES.  239 

Herbst.  It  consists  of  a  German  silver  ring^  soldered 
with  tin,  which  fits  exactly  to  the  neck  of  the  tooth.  Un- 
fortunately however,  this  metallic  ring  has  the  disad- 
vantage of  darkening  the  field  of  operation.  This  sug- 
gested the  manufacture  of  a  ring  from  a  transparent 
material,  such  as  the  Kohmoor  matrix  Avhich  is  now  for 
sale  on  the  market  (Fig.  118  a.).  This  transparent  ring 
permits  a  full  view  of  the  tooth,  but  as  it  is  made  of  cellu- 
loid, it  is  too  soft  to  withstand  the  pressure  necessary  for 
gold  filling.  Its  employment  is  therefore  limited  to 
fillings  of  plastic  material. 


'-'-•"'SI    I^SB     ^SSI    ^SS    ;^g^ 


Fig.  119. — a,  a  twisted  roll  of  non-cohesive  gold-foil ;  b,  the  same  roll  cut 
into  sections :  c,  compression  of  the  non-cohesive  cylinders  of  gold  which  have 
been  introduced  into  the  cavity. 

An  exact  fitting  ring  consists  in  a  metallic  strip,  placed 
around  the  tooth  to  be  filled,  which  may  be  shaped  into  a 
ring  by  means  of  a  screw  appliance.  The  small  appara- 
tuses of  Pinney,  Brophy,  Meister  and  others,  are  of  this 
variety.  If  it  is  necessary  at  one  sitting  to  fill  the  cavities 
of  two  neighboring  approximal  surfaces,  the  matrix  of 
Miller  is  the  most  suitable  (Fig.  118  6.). 

This  consi.sts  of  two  metallic  strips  soldered  together  at 
one  end,  between  which,  in  order  to  fix  them  in  place,  a 
metallic  peg  or  wooden  C(Mie  is  inserted. 

A  similar  instrument  has  been  devised  by  Herbst.  The 
employment  of  matrices  in  gold  fillings  is  limited.  They 
are  occasionally  indispensable  in  filling  approximal  cav- 
ities in  the  cervical  region.  However,  as  soon  as  a  layer 
of  the  ffold  has  been  built  it  is  more  convenient  to  com- 


240  THE  TECHNIC  OF  FILLING   OF  TEETH. 

plete  the  operation  without  a  matrix,  for  it  is  very  difficult 
to  compress  the  gold  with  sufficient  force  at  the  edges 
without  displacing  the  apparatus.  The  construction  of 
large  contours  with  amalgam  is,  however,  much  easier  by 
using  a  matrix  and  it  is  in  such  fillings  that  it  finds  its 
true  sphere  of  usefulness.  Cement  fillings  may  be  inserted 
in  all  cases  without  applying  a  matrix.  Plate  24  shows 
the  application  of  a  simple  band-matrix  to  the  front  teeth. 

FILLING  WITH  NON-COHESIVE  GOLD. 

Formerly  cavities  were  filled  much  more  frequently  with 
non-cohesive  gold  than  at  present,  for  it  has  been  found  that 
such  filling  material  is  much  softer  than  cohesive  gold, 
and  that  therefore  the  surfaces  of  such  fillings  later  become 
rough  and  deformed.  A  still  greater  disadvantage  is  the 
fact  that  this  form  of  gold  does  not  permit  the  construction 
of  a  contour.  Yet,  because  of  its  softness  it  adheres 
closely  to  the  walls  and  thus  securely  closes  the  cavity. 
On  account  of  this  property  many  practitioners  use  it  to 
cover  the  fioor  and  the  lateral  walls  of  a  cavity.  They 
complete  the  filling,  however,  with  cohesive  gold.  The 
non-cohesive  gold  is  more  easily  compressed  than  the 
cohesive  and  therefore  such  a  filling  is  more  rapidly 
introduced.  It  is  especially  suitable  in  approximal  cav- 
ities, which  are  not  sufficiently  visible,  for  proper  con- 
densation of  the  cohesive  gold  in  all  places. 

The  soft  gold,  purchasable  in  foils,  is  folded  into  three 
or  four  angled  pieces  and  rolled  into  cylinders,  or  as  has 
been  described  in  the  case  of  tin-gold,  is  twisted  M'ith  the 
fingers  into  a  cord  (Fig.  119,  6).  The  latter  is  cut, 
before  use,  into  sections,  which  are  of  such  length  that 
when  inserted  they  extend  somewhat  above  the  upper 
edge  of  the  cavity  (Fig.  119,  6). 

If  it  is  intended  to  fill  only  a  small  cavity  with  non- 
cohesive  gold,  it  is  best  to  employ  a  piece  of  the  gold  cord 
which  will  protrude  a  distance  equal  to  one-third  of  the 
depth  of  the  cavity.  This  small  piece  must  be  of  sufficient 
thickness  to  just  permit  forcing  it  into  the  cavity.     It  is 


PILLING   WITH  NOK-COBESIVE  GOLD.  241 

introduced  in  the  manuer  that  a  cork  is  inserted  into  a 
bottle,  so  that  one  end  rests  upon  the  floor  and  the  other 
protrudes  from  the  cavity.  Next,  as  thick  agokl-plugger 
as  possible  is  thrust  in  between  the  tooth-wall  and  the 
gold,  by  means  of  which  an  energetic  side  motion  is 
exerted  which  presses  the  gold  tightly  upon  the  opposite 
wall  of  the  cavity.  If  this  portion  remains  fast,  the 
manipulation  is  repeated  until  the  walls  which  are  still 
bare  are  covered  with  gold.  The  space  which  then 
remains  in  the  center  is  also  filled  with  a  similarly  shaped 
cylinder,  the  so-called  "key."  The  portion  of  the  metal 
wdiich  protrudes  is  then  forced  down  with  strong  hand 
pressure  and  blows  from  the  mallet.  The  principles  of 
this  filling,  at  least  so  far  as  one  picture  can  show  the 
different  stages  of  a  complicated  process,  are  demonstrated 
in  Fio^.  119  e. 

Usually  at  this  stage  the  filling  is  still  too  high  ;  it  must 
be  dressed  down  with  stones  or  finishing  burs,  and  then 
burnished  or  polished. 

The  principle  of  this  operation  is  the  same  in  big  cavities 
only  it  is  often  impossible  to  make  a  single  portion  of  gold 
remain  tightly  in  place.  Tliis  difficulty  is  made  easier  by 
first  applying  several  pieces  of  gold  to  a  wall.  These 
tend,  then,  under  compression  to  hold  each  other  in  place. 
In  the  same  manner  the  second  portion  as  well  as  the  key 
must  be  composed  of  several  pieces  of  gold.  It  is  also 
j)ermissible  to  set  pieces  of  gold  side  by  side  in  a  row 
along  the  Avhole  wall,  and  Avhen  the  cavity  is  thus  lined 
with  gold  according  to  the  established  •  principles,  the 
filling  is  continued  toward  the  center.  In  the  case  of 
caries  profunda,  that  is,  in  very  deep  cavities,  the  floor 
must  be  first  filled  with  gold  and  in  the  same  way  as  if  a 
small  cavity  were  being  filled.  Thus  a  shalloAv  cavity  is 
formed  whicii  is  easily  filled  in  the  manner  descril)ed  above. 

It  is  important  wlien  soft  gold  is  used  to  condense  it 
always  toward  the  walls.  At  fir.st  this  is  done  according 
to  the  above  method  ;  after  a  large  portion  of  the  cavity 
is  once  filled  a  cone-shaped  })lngger  is  forced  into  the  gold 
in  order  to  press  that  metal  toward  the  walls. 
16 


242 


THE  TEGHNIC  OF  FILLING   OF  TEETH. 


A  description  of  the  method  of  filling  with  a  com- 
bination of  tin  and  gold  may  be  properly  omitted  here,  as 
it  is  similar  to  that  of  non-cohesive  gold. 

FILLING  WITH  COHESIVE  GOLD. 

Cohesive  gold  has  been  universally  adopted  for  filling 
cavities.  It  requires  on  the  part  of  the  o])erator  per- 
severance and  skill,  and  on  the  part  of  the  patient, 
patience  and  repose.  If  any  of  these  requirements  are 
absent,  a  perfect  filling  cannot  be  made,  and  a  poor  gold 


i  ■  c  </  e 

Fig.  120.— Pluggers  for  condensing  gold. 


/ 


filling  is  worse  than  a  mediocre  cement  or  amalgam  fill- 
ing. Aside  from  these  requisites  a  number  of  other  pre- 
liminary conditions  are  necessary  in  order  to  guarantee  a 
satisfactory  filling.  The  teeth  must  not  be  sensitive  to 
pressure  or  hammering,  and  the  tooth  substance  must 
possess  a  tolerable  amount  of  mechanical  resistive  power. 
Furthermore  it  must  be  possible  to  make  the  cavity  per- 
fectly visible  and  absolutely  dry.     If  one  attempts  to  fill 


FILLING    WITH  COHESIVE  GOLD.  243 

a  cavity  with  gold  without  observing  these  cardinal  con- 
ditions he  makes  a  failure  which  will  not  be  without 
untoward  results. 

Cohesive  gold  is  given  a  cohesive  property  by  heating. 
It  should  be  heated  or  annealed  directly  before  using  by 
placing  it  in  a  sheet  of  mica  plate,  and  holding  this  for  a 
short  time  over  the  flame  of  a  spirit  lamp. 

The  instruments  which  are  now-a-days  employed  for 
condensing  cohesive  gold  are  so  constructed  that  they  may 
be  used  both  by  hand  or  with  a  mallet.  The  beginner 
who  attempts  to  select  gold-pluggers  from  a  catalogue  is 
perplexed  because  of  an  embarrassment  of  riches,  for  in  it 
he  finds  for  sale  all  imaginable,  practical  and  impractical, 
instruments.  In  order  to  save  the  student  unnecessary 
expense  when  buying  his  instruments  we  present  six  hand 
pluggers  which  are  sufficient  for  nearly  all  cases.  1.  A 
broken-off  excavator  which  tapers  to  a  point  (Fig.  120  a). 
This  instrument  is  very  useful  in  narrow  close  cavities. 


Fig.  121.— Hand  maUet  for  condensing  gold. 

In  anterior  approximal  cavities,  especially  in  order  to  con- 
dense the  gold  against  the  labial  wall,  the  screw-like  plug- 
ger  (6)  is  employed.  For  compressing  the  filling  in  areas 
walled  off  by  the  operator,  the  bayonet-formed  plugger  (e) 
usually  gives  the  best  service,  and  in  areas  which  are 
already  walled  off,  the  plugger  (c/)  which  is  bent  at  an 
obtuse  angle  suffices.  The  filling  of  a  superficial  cavity 
as  a  rule  is  readily  condensed  with  the  muzzle-shaped 
plugger  (e),  and  that  of  a  cavity  at  the  neck  of  the  tooth 
with  the  foot  plugger  (/). 

Of  all  mallets  the  ordinary  hand  mallet  is  to  be  pre- 
ferred, Fig.  121,  for  only  by  means  of  it  has  one  the 
power  of  altering  momentarily  the  rapidity  and  the 
strength  of  each  blow.      Many  dentists  manipulate  the 


244         THE  TECHNIC  OF  FILLING   OF  TEETH. 

hammer  themselves,  yet  the  gold-plugger  is  much  more 
easily  guided  when  an  assistant  attends  to  it.  It  is  claimed 
for  the  so-called  automatic  mallets  that  they  are  not  only 
a  substitute  for  the  assistant  but  permit  more  rapid  work. 
ThepneumatiG  mallet  devised  by  Kirby  is  very  ingenious. 
It  consists  of  a  bolt,  which  is  driven  forward  to  strike 
upon  the  point  of  the  plugger.  A  most  useful  instrument 
is  constructed  by  supplying  this  hammer  with  the  head 
devised  by  Rauhe,  which  makes  it  possible  to  strike  blows 
from  all  conceivable  angles.  Its  failure  of  general  adop- 
tion is  probably  due  to  the  fact  that  it  requires  an  India- 
rubber  bulb  or  bellows,  which  being  operated  by  the  foot 
is  very  fatiguing.  But  if  in  place  of  it,  the  Kirby-Rauhe 
hammer  is  connected  with  a  small  air  pump,  which  is 
applied  to  the  drilling  machine,  rapid  and  satisfactory 
blows  are  struck  without  exhausting  the  operator.  Such 
a  hammer  is  illustrated  without  the  hand  piece  which 
belongs  to  it,  in  Fig.  122. 


Fig.  122.— Kirb3'-Rauhe's  automatic  gold  hammer  for  pneumatic  power. 

Of  the  other  hammers  which  are  operated  by  the  den- 
tal engine  those  of  Power,  Buckingham,  Elliot  and 
Bonville  are  the  most  successful.  The  electric  hammer 
of  Bonville  and  Webb  is  preferred  by  some  operators. 
The  most  difficult  phase  of  the  completion  of  a  cohesive 
p-old  fillina:  is  the  besrinniuo;,  and  nowhere  can  the  axiom 
"■  omne  pi'incipium  grave"  be  more  appropriately  applied 
than  here.  It  is  not  to  be  wondered,  therefore,  that  all 
possible  means  have  been  resorted,  to  in  .searching  for 
assistance,  and  every  practical  dentist  possesses  his  own 
trick  or  method  for  fixing  the  first  piece  of  gold.  Many 
begin  the  filling  with  soft  gold,  or  simply  with  unheated 


FILLING   WITH  COHESIVE  GOLD.  245 

cohesive  cylinders,  Avhich  possesses  properties  similar  to 
soft  gold,  and  after  the  first  portion  adheres,  the  operation 
is  completed  with  cohesive  gold,  which  clings  tightly  to 
the  former.  Rather  wide  pluggers  are  required  to  press 
the  gold  against  the  walls  and  the  floor  of  the  cavity. 
By  that  we  mean  pluggers  with  broad  surfaces  and  fine, 
shallow  serrations. 


Fig.  123. — Enlargement  of  the  cavities  for  the  reception  of  cohesive  gold,  with 
or  without  under-cuts. 

The  question  of  securing  anchorac/e  points,  under-cuts 
etc.,  may  be  settled  by  stating  that  they  are  only  neces- 
sary in  those  cases  in  which  the  conditions  of  the  cavity 
has  not  sufficient  anchorage.  In  central  cavities  of  all 
types  (Fig.  1 23  a  and  b ),  whether  they  are  cyliud  rical  or  fun- 
nel-shaped, it  is  unnecessary  to  make  under-cuts  provided 
the  cross-cut  drill  is  employed.  This  instrument  forms 
numerous  although  shallow  attachment  grooves,  as  is  shown 
in  Fig.  123.  If,  however,  the  operation  is  done  with 
ordinary  burs,  the  funnel-shaped  cavities  must  be  indented 
with  the  wheel-bur  (Fig.  123  c). 

In  approxiraal  cavities  the  under-cuts  should  be 
made,  but  only  in  regions  which  are  thoroughly  visible, 
and  in  which  the  gold  can  be  carefully  conden.sed. 
Especial  care  is  required  in  forming  under-cuts  in  the 
front  teeth,  for  the  thinness  of  their  crowns  may  easily 
weaken  the  walls  of  the  cavity.  There  is  also  danger 
of  drilling  near  to,  or  into  the  pulp,  a  mishap  which 
happens  quite  frequently  to  beginners.  The  best  fixa- 
tion groove  is  in  the  cervical  portion  directed  toward 
the  cervix  of  the  cavity.  It  is  formed  by  penetrating 
with  a  small  bur  between  the  enamel  and  \n\\\),  and 
parallel    to  the  latter  in  such  a  manner  that  neither  the 


246         THE  TECHNIC  OF  FILLING   OF  TEETH. 

enamel  is  weakened  nor  the  pulp  cavity  encroached  upon. 
A  second  retention  point,  provided  of  course  that  it  does 
not  cause  the  crown  to  become  too  weak,  is  made  in  that 
part  of  the  dentin  which  lies  between  the  pulp  and  the 
incisal  edge  of  the  tooth.  As  the  tooth  is  very  thin  in  this 
area  care  should  be  taken  not  to  perforate  the  labial  or  lin- 
gual enamel  covering,  which  would  very  much  compli- 
cate the  process.  These  two  anchorage  points  are  shown  in 
Fig.  123cZ. 

The  notches  selected  for  the  purpose  of  attachment  are 
usually  filled  with  a  strip  or  cylinder  of  cohesive  gold, 
which  is  tightly  compressed  by  means  of  a  fine  plugger. 
After  this  first  small  piece  has  been  so  tightly  attached 
to  the  floor  of  the  groove  that  it  remains  securely  in 
position,  then  a  second  piece  is  placed  upon  the  first, 
and  a  third  portion  of  gold  upon  the  second,  and  so  on, 
until  the  fixation  point  or  groove  is  tightly  and  completely 
filled.  Each  individual  piece  of  gold  must  be  compressed 
by  means  of  a  fine  pointed  instrument  upon  which  very 
light  blows  are  struck.  When  the  fixation  area  has  been 
filled,  a  slightly  heated,  somewhat  larger  cylinder  of  gold 
is  brought  into  the  cavity,  and  fixed  with  the  pointed 
plugger  to  the  gold  in  the  retention  and  then  pressed  with 
a  wider  plugger  against  the  walls  of  the  cavity.  With 
the  completion  of  this  procedure,  the  most  difficult  feature 
of  the  filling  has  been  overcome,  and  the  remainder  of  the 
operation  progresses  rapidly.  It  is  of  the  greatest  im- 
portance that  each  newly-introduced  piece  of  gold  should 
adhere  tightly  to  that  already  placed  within  the  ca\'ity, 
and  that,  simultaneous  with  condensation,  larger  and  larger 
surfaces  of  the  cavity  should  become  covered  with  gold. 
The  secret  of  constructing  a  successful  filling  depends 
exclusively  upon  maintaining  a  proper  relationship  between 
these  two  conditions.  Introducing  too  large  masses  of 
gold  upon  the  fixation  area  gives  the  filling  a  spherical 
form.  Fig.  124«.  In  this  case  it  is  almost  impossible  to 
subsequently  establish  an  air-tight  union  with  the  tooth- 
wall,  for  the  small  piece  of  gold,  which  is  later  introduced 
between  the  condensed  gold  and  the  cavity   wall,  rapidly 


FILLING    WITH  COHESIVE  GOLD.  247 

becomes  stiff  and  cannot,  therefore,  properly  adapt   itself 
to  the  narrow  groove. 

If,  on  the  contrary,  the  gold  in  the  under-cut  has  not 
been  properly  condensed  and  a  large  portion  of  the  cavity 
immediately  covered  with  a  thin  layer  of  gold,  the  latter 
tends  to  become  loosened  from  the  walls  of  the  cavitv, 
while  the  rest  of  the  filling  is  being  constructed  (Fig.  1 24^). 
The  failures  which  are  experienced  soon  teach  one  how 
much  gold  may  be  condensed  against  the  fixation  groove, 
and  how  much  against  the  walls.  An  attempt  is  made 
in  Fig.  124c  to  show  the  correct  conditions,  that  is,  the 
principles  which  must  be  considered  in  this  procedure. 
Indeed  these  requirements  are  also  applicable  in  filling 
central  as  well  as  approximal  and  labial  cavities. 


^ 


a  6  c 

Fig.  124.— <■(,  the  condensing  of  the  gold  has  been  limited  too  much  to  the 
under-cut  (fixation  groove),  and  it  has,  therefore,  become  rolled  into  a  ball ; 
b,  in  this  case,  on  the  contrary,  the  gold  in  the  under-cut  has  not  been  suffi- 
ciently condensed,  and  the  building  up  of  the  walls  was  begun  too  soon,  with 
the  result  that  the  gold  layer  became  contracted  and  drawn  away  from  the 
walls ;  c,  here  the  proper  conditions  have  been  observed  and  a  satisfactory 
result  obtained. 

The  filling  of  very  large  cavities  is  rather  complicated, 
and  the  process  is  demonstrated  in  Fig.  125.  At  first  the 
fixation  point  and  its  neighborhood  is  filled,  and  then  the 
gold  is  deposited  between  this  layer  and  the  opposite  wall, 
(6).  Finally  the  gold  is  spread  in  layers  over  this  in  such 
a  manner  that  it  Avill  join  the  two  portions  which  were 
first  introduced.  This  is  repeated  until  the  cavity  is  com- 
pletely filled. 

Unfortunately  the  .size  of  this  work  does  not  permit  a 
discussion  in  greater  detail  of  this  very  important  subject. 

The  author's  own  method  of  inserting  a  gold  fiUing  is 
shown  in  Fig.  127,  which  represents,  somewhat  enlarged, 
an  incisor  tooth  crown  with  an  approximal  filling.     Two 


248 


THE  TECHNIG  OF  FILLING   OF  TEETH. 


under-cuts  are  made.  The  steps  of  the  process  are  as 
follows  :  At  first  a  small  piece  of  crystal-gold  is  laid  on 
the  floor  of  the  upper  under-cut  and  then  condensed  into 
a  firmly-attached  plug  by  means  of  light  blows.  A  broad 
plugger  is  employed  to  spread  the  crystal-gold  in  front 
of  the  fixation  notch,  and  by  means  of  a  pointed  plugger, 
it  is  condensed  into  the  notch.  We  cannot  be  too  emphatic 
in  recommending  the  filling  of  the  fixation  grooves  partially 
or  completely  with  crystal-gold.  For  it  attaches  itself 
almost  immediately  and  prevents  the  struggle  between 
the  operator  and  the  first  portion  of  gold,  as  one  often 
sees  even  with  the  experienced  dentist,  to  the  detriment 


Fig.  125.— The  vari- 
ous stages  in  the  fill- 
ing of  a  large  central 
cavity  with  gold. 
a,  first;  6,  second; 
e,  third  ;  d,  fourth 
layer  of  gold. 


Fig.  126.— The  various 
stages  in  filling  with  gold 
an  incisor  approximal 
cavity  which  is  not  too 
large  ;  a,  first ;  6,  second ; 
c,  third  layer  of  gold. 


Fig.  127.— The  various 
steps  taken  in  filling 
with  cohesive  gold  a 
large  approximal  cavity 
of  an  incisor  tooth  :  a, 
crystal-gold  and  small 
gold  cylinder ;  6,  larger 
gold  cylinder :  c,  crystal- 
gold  and  small  gold  cyl- 
inder; d,  large  gold  cyl- 
inder (slightly  heated) ; 
e,  gold  foil  No.  4  0, 
(strongly  heated). 


of  the  filling.  Letter  a,  in  Fig.  127,  indicates  the  position 
of  the  crystal-gold  upon  which  at  first  small  cylinders  of 
gold  about  the  diameter  of  the  under-cut  are  hammered. 
These  cylinders  are  but  slightly  heated,  and  must  not  be 
made  too  firm.  Next  larger  cylinders  (6)  are  placed  upon 
the  upper  under-cut,  Avhich  is  now  filled  with  gold.  These 
cylinders  are  successively  compressed  from  the  point  of 
attachment  to  the  lingual  wall  of  the  cavity.      The  rule 


FILLING   WITH  COHESIVE  GOLD.  249 

holds  good  here,  as  it  does  in  working  with  non-cohesive 
gold,  that  the  visible  portion  should  be  covered  first.  If, 
on  the  contrary,  the  labial  wall  were  first  covered  with 
gold,  aside  from  the  development  of  other  inconveniences, 
the  entrance  of  the  liglit  would  be  cut  off.  As  soon  as 
the  work  has  progressed  so  far  that  the  gold  reaches  the 
neighborhood  of  the  lower  under-cut,  it  becomes  necessary 
to  fill  this  with  crystal  and  cylindrical  gold  in  the  same 
manner  as  in  the  upper  notch.  This  is  demonstrated  in 
Fig.  127  e.  Thus  the  upper  is  finally  closely  united  with 
the  lower  under-cut,  after  which  the  further  upbuilding 
of  the  filliug  presents  no  difficulties.  The  area,  at  d,  is 
filled  with  larger  cylinders,  but  it  must  be  remembered 
that  each  cylinder  must  be  carefully  condensed  by  itself 
before  a  second  is  introduced. 

After  the  cavity  has  been  filled  with  larger  cylinders 
until  a  certain  level  {d)  is  reached,  the  operation  should  be 
completed,  in  order  to  secure  a  fairly  uniform  surface,  by 
constructing  the  contour  with  thicker  foil,  No.  40.  This 
foil  being  folded  into  three  or  four  angled  pieces,  which 
are  approximately  the  size  of  the  surface  of  the  cavity. 
Uj)  to  this  stage  the  gold  has  been  condensed  with  the 
ordinary  mallet  or  with  hand  pressure,  during  which  the 
handle  of  the  hand  plugger  must  be  moved  to  and  fro 
while  the  point  remains  stationary.  By  means  of  this 
motion  it  is  alone  possible  to  obtain  a  uniform  conden- 
sation, for  it  permits  not  only  the  edge  of  the  plugger  but 
also  its  whole  surface  to  act  upon  the  gold.  The  last  foil 
used  should  be  strongly  heated  in  order  to  increase  the 
hardness  of  the  contour.  The  automatic,  or  hand  mallet, 
gives  better  service  here  than  hand  pressure  in  securing  a 
rapid  and  uniform  condensation  of  the  refined  gold  Avhich 
lies  on  tlie  surface. 

Herbst  has  suggested  a  method  of  condensation  of 
the  gold  by  means  of  rotation.  According  to  his  method, 
the  gold  is  burnished  within  the  cavity  by  means  of  a 
smooth  instrument,  driven  by  the  dental  engine.  This 
rotary  movement  requires  an  assistant,  but  saves  much 
time  and  is  decidedly  more  agreeable  to  the  patient. 


250 


THE  TECHNIC  OF  FILLING   OF  TEETH. 


THE  FINISHING  OF  A  GOLD  FILLING. 

The  careful  finishing  of  a  gold  filling  is  fully  as 
important  as  any  other  part  of  the  operation.  Fillings 
which  have  not  been  properly  finished  have  a  very 
unsightly  appearance,  and  what  is  more  harmful,  permit 
remnants  of  food  to  cling  to  the  uneven  surface  and 
to  the  edges  which  project  over  the  enamel.  The  oral 
bacteria  soon  cause  the  food  to  undergo  degeneration, 
whereby  products  are  formed  which  have  an  injurious 
action  upon  the  teeth.  As  a  result,  a  recurrence  of  caries 
arises  in  the  course  of  time  at  the  edges  of  such  poorly 
finished  teeth. 


ti  i 


a  ft  -  c 

Fig.  128. — Plug  finishing  burs  which  are  employed  in  working  upon  the 
occlusal  surface  of  a  gold  filling. 

In  order  to  give  a  tooth  its  original  appearance  as 
nearly  as  possible,  the  masticating  surface  of  central 
cavities  must  be  given  a  concave  form.  Such  cavities 
are  usually  filled  too  high,  and  must  therefore,  according 
to  the  foregoing  law,  be  cut  down.  In  order  to  detect 
the  longest  articulating  point,  a  small  piece  of  carbon 
paper  is  placed  between  the  teeth  and  the  patient  is 
requested  to  bite.  That  portion  of  the  surface  of  the 
gold  which  shows  a  black  point  indicates  the  area 
which  must  be  ground  down.  For  this  purpose  the 
steel-finishers  shown  in  Fig.  128  are  employed.  Mandrels 
carrying  emery,  corundum  and  carborundum  points  are 
also   resorted   to   for  reducing  the  filling  to  the  proper 


THE  FISISHiyG   OF  A    GOLD  FILLING.  251 

occlusion.  All  of  these  grinding  substances  when  applied 
in  the  dry  state  produce  heating  of  the  tooth;  it  is  there- 
fore advisable  to  keep  the  stone  wet. 

This  is  easily  accomplished  by  an  ordinary  water  syringe 
(Fig.  129)  hekl  by  an  assistant.  In  the  application 
of  these  grinding  materials,  the  first  object  is  to  cause 
the  surface  of  the  gold  to  pass  smoothly  into  that  of 
the  enamel,  and  shape  it  so  that  the  antagonist  will 
no  longer  strike  it  too  forcibly.  The  filling  must 
moreover  be  as  smooth  as  a  mirror,  and  this  can  only 
be  accomplished  by  means  of  steel  polishers.  It  is 
also  useful  to  employ  small  points  and  wheels  of  wood, 
leather,  felt,  etc.  which  are  covered  with  some  polishing 
substance  such  as  pulverized  emery,  prepared  chalk,  etc. 


Fig.  129.— Water  syringe. 

Labial  and  especially  approximal  fillings  must  be 
given  a  convex  form.  Where  space  permits  the  applica- 
tion of  fine  paper  disks,  the  operation  is  performed  in 
exactly  the  same  manner  as  in  the  case  of  fillings  of 
the  masticating  surface,  that  is,  the  filling  is  first  cut 
down  to  the  level  of  the  enamel  at  the  edges  and  then 
given  a  high  polish.  This  is  carried  out  with  greater 
difficulty  at  the  neck  of  the  tooth,  both  because  the 
sensitive  gum  stands  in  the  way  and  because  the  tooth 
is  contracted  in  this  region,  which  interferes  in  reaching 
the  neck  of  the  tooth  with  the  finishing  material.  Many 
dentists  remove  the  excess  of  gold  at  this  point  with 
thin  bladed,  curved  gold  trimmers,  but  better  than  these, 
when  the  surface  can  be  readily  reached,  are  strips  of 
emery  pajier  or  cuttlefish-cloth  strips. 


252  THE  TECHNIC  OF  FILLING   OF  TEETH. 

AMALGAM  FILLINGS. 

It  is  a  simple  task  to  introduce  amalgam  fillings 
for  the  substance  employed  is  a  plastic  material,  that  is, 
it  is  in  a  soft  dough-like  state.  The  ease  with  which 
this  filling  is  made,  has  unfortunately  caused  much 
bung-lino;;  and  has  therefore  resulted  in  a  loss  of  confidence 
of  the  laity.  To  obtain  a  properly  fitting  amalgam  filling, 
the  cavity  must  be  as  thoroughly  prepared  as  for  a  gold 
filling,  only  the  fixation  grooves  may  be  omitted  provided 
the  cavity  possesses  a  form  which  will  retain  the 
filling.  The  instruments  include  old  gold  pluggers, 
polishers,  etc.  A  good  set  of  instruments  is  shown  in 
Fig.  130.  It  consists  of  six  instruments.  They  are, 
(a)  which  is  a  double-ended  instrument  with  broad  coarse 
points  which  are  bent  at  nearly  right  angles.  It  is 
very  useful  for  introducing  pieces  of  amalgam  into  the 
upper  molars.  For  the  purpose  of  pressing  the  amalgam 
into  the  cavity  and  rubbing  it  to  place,  the  instruments 
(6),  (c)  and  {d)  are  employed.  The  instrument  {e)  is  very 
useful ;  the  rounded  end  for  pressing  the  amalgam  into 
the  cavity,  and  the  wing-like  process  for  making  the 
surface  of  approximal  fillings  smooth.  The  spatula  (/) 
is  indispensable  for  approximal  fillings. 

A  description  of  these  instruments  really  explains  the 
technie  of  the  filling.  The  thoroughly  kneaded  amalgam 
is  formed  into  little  pieces  which  must  be  decidedly 
smaller  than  the  ca\dty  itself.  Of  these  at  first  one  is 
introduced  into  the  cavity  and  rubbed  tightly  against  the 
walls.  This  first  piece  is  followed  by-  a  second,  then  a 
third,  and  so  on  until  the  cavity  is  filled. 

Usually  the  amalgam  is  mixed  wdth  too  much  mercury 
which  gives  it  too  soft  a  consistency.  This  evil  may  be 
met  by  condensing  the  amalgam  with  small  pieces  of 
bibulous  paper  instead  of  steel  instruments.  This  causes 
the  excess  of  mercury  to  appear  on  the  surface  in  the  form 
of  small  globules.  The  same  object  may  be  attained  by 
absorbing  the  surplus  mercury  with  tin,  or  gold  foil,  or  it 
may  be  wiped  off  with  small  pledgets  of  cotton.     The 


A3IALGAM  FILLINGS. 


253 


finishing  of  an  amalgam  filling  is  performed  in  the  same 
manner  as  for  gold,  only  the  mass  must  first  become 
thoroughly  hardened,  which  requires  several  days. 


r 


Fig.  130. 


Aside  from  the  pure  form,  amalgam  is  employed  in 
.several  combinations.  They  consist  (1)  of  a  mixture  with 
some  other  material  in  order  to  combine  the  properties  of 
both.  A  satisfactory  filling  material  of  this  sort  consists 
of  a  mixture  of  zinc  phosphate,  cement,  and  amalgam.  It 
clings  to  the  walls  of  the  cavity  like  cement,  is  a  poor 


254 


THE  TECHNIC  OF  FILLING   OF  TEETH. 


conductor  of  heat,  and  is  about  as  resistive  as  amalgam 
fillings.  This  filling  material  is  introduced  according  to 
the  same  principles  as  amalgam.  (2)  Another  variety 
of  combination  consists  in  filling  one  part  of  the  cavity 
with  guttapercha  or  cement,  and  the  remaining  portion 
with  amalgam.  Where  the  gums  cover  the  teeth  that  is, 
in  the  cervical  region,  amalgam  fillings  are  very  rapidly 
destroyed  (especially  copper  amalgam)  and  therefore  gutta- 
percha is  more  serviceable  in  that  region  (Fig.  131  a). 
An  advantageous  combination  consists  in  placing  a  pro- 
tecting layer  of  guttapercha  or  cement  on  the  floor  of  the 


Amalgam 
Guttapercha 


Am.algain 
Guttapercha 


"^Guld 

|-'  .^Amalgam 


cavity  in  caries  profunda,  and  then  completing  the  filling 
with  amalgam  or  gold  (Fig.  131  6).  When  weak  walls 
or  other  conditions  prevent  the  filling  of  large  cavities, 
such  as  an  approximal-central  cavity  with  gold,  a  more 
or  less  thick  layer  of  amalgam  should  first  be  applied, 
and  the  operation  finished  with  gold  as  shown  in  Fig. 
131  c.  Some  operators  place  the  gold  directly  into  the 
amalgam  when  still  soft,  with  the  idea  that  the  first  layers 
should  become  amalgamated,  and  that  later  it  is  possible 
to  complete  the  filling  as  if  it  were  composed  wholly  of 
gold.  This  method,  however,  lacks  the  firm  foundation 
which  is  necessary  for  the  correct  construction  of  a  gold 
filling.  It  seems  much  wiser  to  permit  the  lower  layer 
of  amalgam  to  harden  for  several  days,  and  at  the  expi- 
ration of  that  time  to  hammer  the  gold  upon  it.     A  good 


PORCELAIN  FILLINGS.  255 

cement  as  the  foundation  is  preferable  even  to  the  hard- 
ened amalgam  in  most  instances. 


CEMENT  FILLINGS, 

The  same  principles  must  be  observed  in  the  prepara- 
tion of  the  cavity  for  the  reception  of  a  cement  filling  as 
for  amalgam.  All  carious  dentin  must  be  removed  as 
carefully  as  possible  and  the  cavity  thoroughly  dried. 
Under-cuts  are  not  ahvays  necessary  ;  at  any  rate  they 
need  not  be  as  deep  as  for  the  retention  of  gold  or  amal- 
gam, because  cement  being  an  adhesive  material  sticks 
firmly  to  the  tooth-substance.  Because  of  this  property 
of  adhering  to  the  tooth-substance,  cement  is  probably 
the  best  filling  material   for  cavities  with  weak   walls. 

The  same,  or  similar  instruments  are  employed  as  for 
amalgam  fillings,  although  the  spherical  and  the  spade- 
shaped  tools  are  preferred.  This  material  is  most  con- 
veniently applied  when  the  liquid  has  absorbed  enough 
powder  to  form  a  mass  which  can  be  moulded  like  amal- 
gam. From  this  mass  small  pellets  are  formed  which, 
because  of  the  tendency  to  rapidly  harden  must  be  intro- 
duced into  the  cavity  as  quickly  as  possible.  The  finish- 
ing of  the  filling  is  similar  to  that  of  the  amalgam  fillings, 
but  is  not  performed  until  the  cement  has  become  hard. 


PORCELAIN  FILLINGS. 

The  search  for  an  ideal  filling  material  led  to  the 
employment  of  enamel,  glass,  and  porcelain.  With 
reference  to  their  appearance,  properly  prepared  porcelain 
fillings  are  practically  ideal,  and  are  therefore  mainly 
used  in  visible  regions.  Of  those  who  advocate  the  use 
of  this  form  of  filling,  some  prefer  to  employ  already 
prepared  pieces  of  porcelain,  while  others  first  melt  this 
substance  in  a  mould,  or  matrix,  which  has  been  adapted 
to  the  form  of  the  cavity. 

A  useful  filling  may  be  obtained  by  grinding  a  piece 
of  the  right  size  out  of  an  artificial  tooth.     It  must  be 


256         THE  TECHNIO  OF  FILLING   OF  TEETH. 

borne  in  mind,  however,  that  such  a  piece  of  enamel  must 
fit  as  exactly  into  the  cavity  as  possible.  Cavities  Avhich 
are  almost  round  may  be  given  circular  form,  then  a  piece 
of  porcelain,  which  fits  the  cavity  exactly,  is  introduced  and 
fastened  in  place  by  means  of  cement.  Those  who  do  not 
possess  sufficient  practice  and  patience  for  this  purpose,  may 
obtain  already  prepared  enamel,  out  of  which  disks  of  the 
required  size  may  be  easily  ground.  Dall  has  manufa(;- 
tured  enamel  rods  of  various  forms,  round,  oval,  crescentic, 
etc.  These  are  very  useful,  and  are  suitable  for  nearly 
all  varieties  of  labial  defects.  If  a  whole  corner  of  a  tooth 
is  to  be  replaced,  it  is  preferable  to    employ    a    fragment 


Fig.  132. — a,  approximal  cavity  prepared  for  the  reception  of  an  enamel  fill- 
ing; beside  it  is  the  fillina:  material  of  melted  enamel  supplied  with  a  reten- 
tive under-cut;  6,  labial  defect,  which  has  been  drilled  into  the  circular  form 
for  the  reception  of  an  enamel  dislc;  the  latter  is  also  shown. 

from  an  artificial  tooth,  to  which  a  platinum  pin  has  been 
attached.  This  is  introduced  into  the  cavity  in  such  a 
manner  that  it  may  be  tightly  anchored  into  the  cement. 
Various  forms  of  such  tooth  corners  supplied  with  long 
platinum  pins  are  now  sold  to  the  trade.  If  a  sufficiently 
deep  cavity  is  cut  into  the  tooth  in  which  the  peg  may  be 
fastened,  the  filling  obtains  a  much  more  secure  hold  thar 
if  the  pin  is  only  inserted  in  the  cement.  Of  course  if 
the  pulp  has  been  devitalized,  much  larger  and  thicker 
pins  may  be  employed,  reaching  into  the  root  canal. 

At  the  present  day,  however,  fusible  glass  and jjorcela in 
are  more  frequently  employed  than  the  above   described 


PORCELAIN  FILLINGS.  257 

pieces  of  enamel.  To  fill  a  defect  with  this  material  the 
cavity  is  prepared  as  for  any  other  filling,  with  the  excep- 
tion that  it  should  be  given  a  trough-like  form,  without 
under-cuts,  in  order  to  permit  the  securing  of  a  matrix. 
The  mold  is  obtained  with  a  piece  of  gold  or  platinum- 
gold  foil,  jSTo.  60,  a  small  piece  of  which  is  pressed  into 
the  cavity  by  means  of  a  small  piece  of  spunk  or  cotton. 
While  a  small  pledget  of  cotton  is  being  pressed  into  the 
cavity  with  one  hand  in  such  a  manner  that  the  foil  can- 
not be  displaced,  a  steel  polisher  is  used  with  the  other 
hand  to  press  it  on  all  sides  against  the  walls  of  the  cavity. 
If  by  means  of  this  manipulation  an  exact  mold  of  the 
cavity  is  reproduced,  and  it  sets  so  tightly  in  place  that 
it  cannot  be  shaken,  it  may  then  be  carefully  lifted  out  by 
means  of  a  pair  of  plyers.  As  much  porcelain  powder, 
which  has  been  made  into  a  thick  paste  with  distilled 
water,  is  then  introduced  into  this  cup-like  impression  by 
means  of  a  small  spatula,  as  is  necessary  to  obtain  the 
required  height  of  the  filling.  The  whole  mass  is  then 
carefully  and  slowly  heated  over  a  white  flame  or  in  an 
electric  furnace  until  it  melts,  after  which  it  is  allowed 
to  slowly  cool.  If  sufficient  of  this  substance  has  been 
added  the  desired  height  as  well  as  the  form  of  the  edge  are 
obtained.  Should  this  not  be  the  case  a  fresh  mass  should 
be  added  and  the  filling  again  fused.  Various  methods  have 
been  proposed  for  roughening  this  mass  of  enamel  on  that 
side  which  is  turned  to  the  walls  of  the  cavity,  in  order  to 
make  it  more  secure  in  the  cement.  In  the  majority  of 
cases  it  suffices  to  slightly  nick  the  filling  with  a  diamond 
disk. 

^  A  rough  surface  may  also  be  obtained  by  dusting  a 
little  gypsum  on  the  floor  of  the  matrix  before  introducing 
the  porcelain. 

Experience  has  taught  us  that  glass  fillings  discolor  in 
the  course  of  time,  which  is  attributed  to  the  cement  sub- 
stance which  is  employed  ;  but  since  this  phenomenon 
occurs  also  when  perfectly  colorless  cement  is  used,  it  is 
more  probable  that  the  coloring  matter  in  the  filling  itself 
becomes  altered.  The  porcelain  bodies  which  are  melted 
17 


258  THE  TECHNIC  OF  FILLING   OF  TEETH. 

with  difficulty — that  is,  require  a  high  degree  of  heat  to 
fuse  them — are  believed  to  be  the  most  resistive  to  color 
changes. 

GUTTAPERCHA    FILLINGS. 

To  obtain  a  durable  filling  with  guttapercha,  it  must 
only  be  employed  in  places  suitable  for  a  comparatively 
soft  material  and  where  no  pressure  needs  to  be  resisted. 
The  cavity  must  be  prepared  with  as  much  care  as  for 
other  fillings.  Before  inserting  the  guttapercha  no  trace 
of  dampness  should  exist,  for  otherwise  the  filling  will  not 
adhere  to  the  walls  of  the  cavity.  The  guttapercha  is 
introduced  into  the  cavity  in  little  separate  pieces,  which 
are  softened  by  holding  it  over  the  spirit  lamp  for  a 
minute.  By  means  of  a  ball  burnisher  plugger  sufficient 
material  is  then  successively  added  and  pressed  lightly 
into  place  until  the  cavity  is  filled.  The  excess  which 
finally  remains  is  then  removed  by  a  thin  knife-like 
instrument  which  has  been  heated.  In  doing  so  the 
instrument  should  be  directed  toward  the  edge  in  order 
to  elevate  the  marginal  closure.  Many  paint  the  surface 
with  chloroform  in  order  to  obtain  greater  smoothness;  this 
procedure,  however,  causes  the  surface  to  become  rougher 
and  more  easily  destroyed.  Such  fillings,  too,  are  likely 
to  be  applied  without  proper  care,  and  therefore  it  is  not 
surprising  that  in  a  short  time  the  tooth  tissues  which 
underlie  the  filling  undergo  destruction  to  a  larger  extent. 
We  cannot,  therefore,  be  too  emphatic  in  warning  against 
the  careless  employment  of  this  substance  as  a  filling 
material. 

In  our  experience,  guttapercha  is  best  suited  for 
cavities  which  extend  below  the  gum.  In  these  cases 
temporary  guttapercha  under  comparatively  strong 
pressure  is  introduced,  and  allowed  to  remain  for  from 
two  to  three  weeks.  It  exerts  a  constant  pressure 
upon  the  soft  parts  and  leads  to  an  obliteration  of  the 
blood-vessels.  If  after  the  lapse  of  this  time  the  filling 
is  removed,  it  will  be  found  that  the  gum  stands  off, 
and    that   the    neighborhood    of  the    cavity,  as   well   as 


DISEASES  OF  THE  PULP.  259 

the  cavity  itself,  can  be  dried  much  more  easily  than 
previously,  and  that  it  will  then  be  possible  to  introduce 
with  considerable  prospect  of  success,  a  guttapercha 
filling  even  into  a  cavity  which  reaches  far  below 
the  surface  of  the  gums. 

It  is  important  not  to  heat  the  guttapercha  either  more 
or  less  than  is  necessary  for  its  adaptability. 

DISEASES  OF  THE  PULP. 

Of  special  merit  in  connection  with  the  diseases 
of  the  pulp  is  the  work  of  Arkovy  ("  Diagnostik  der 
Zahnkrankheiten ")  in  which  he  studied  and  classified 
the  important  forms  of  lesions  of  this  organ.  Diseases 
of  the  pulp  usually  develop  as  a  sequel  to  caries,  although 
they  have  been  observed  on  rare  occasions  to  follow 
traumatic  influences,  as  for  instance,  the  fracture  of  a 
tooth-crown  or  injury  to  the  pulp  caused  by  a  dental 
instrument.  The  extent  to  which  caries,  even  of  the 
superficial  type,  acts  upon  the  pulp  is  shown  by  the 
development  of  secondary  dentin,  which  is  shown  in 
Fig.  133.  Although  most  authors  believe  that  secondary 
dentin  is  a  physiologic  function  of  the  pulp,  yet  it  is 
also  undoubtedly  the  result  of  pathologic  processes. 
It  is  for  this  reason  that  we  feel  justified  in  calling 
attention  to  it  in  this  place.  Wedge-shaped  defects 
and  abrasions  may  also  lead  to  secondary  formation 
of  dentin  and  indeed  to  pulpitis.  Pulpitis  develops  wlien 
secondary  formation  of  dentin  proceeds  comparatively 
slowly  and  does  not  tend  to  halt  the  further  progression 
of  the  defect.  Concretions  in  otherwise  intact  teeth, 
which  are  known  to  frequently  occur  in  the  pulp,  cause 
remarkably  few  symptoms  ;  here  and  there  however  they 
cause  circulatory  disturbances  which  are  likely  to  injure 
the  pulp.  Atrophia  praecox  and  pyorrhoea  alveolaris 
lead  to  exposure  of  the  roots  through  which  the 
characteristic  so-called  "ascending"  pulpitis  develops. 
Aside  from  these  diseases  of  tlie  pulp  which  arise  in 
consequence    of    local    causes,    other    forms    occur,  the 


260 


DISEASES  OF  THE  PULP, 


Fig.  133.— Development  of  secondary  dentin,    a,  dentin ;  6,  enamel ;  c,  pulp 
cavity ;  d,  superficial  caries  of  enamel ;  e,  secondary  dentin. 


HYPEREMIA   OF  THE  PULP  261 

etiology  of  which  may  be  traced  back  to  constitutional 
diseases  (nervous  disturbances,  gout,  rheumatism,  etc.). 

The  subjective  symptoms  of  a  pulpitis  demonstrate 
themselves  at  the  beginning  by  an  abnormal  sensitiveness 
to  changes  in  temperature,  especially  cold  and  hot  drinks, 
which  call  forth  attacks  of  pain,  as  well  as  sour  and  sweet 
foods,  that  is  irritating  chemical  substances.  Pain  is 
furthermore  caused  by  the  mechanical  action  of  certain 
substances,  as  for  example  the  presence  of  coarse  foods  in 
the  cavity,  or  when  the  tooth  is  touched  with  an 
instrument.  The  diseased  tooth  is  usually,  however, 
not  sensitive  to  tapping,  a  fact  which  is  of  value  in 
distinguishing  diseases  of  the  pulp  from  those  of  the 
periosteum. 

The  pain,  which  originally  lasts  but  a  few"  moments, 
finally  continues  for  hours  and  even  days.  It  may 
spread  to  the  neighboring  regions  to  such  an  extent  that 
tlie  patient  no  longer  feels  it  as  originally  in  any  one 
tooth,  but  in  the  whole  tooth  row  of  the  involved  jaw 
and  even  in  the  opposing  teeth. 

The  most  important  of  the  forms  of  diseases  of  the 
pulp,  classified  by  Arkovy  and  Rothmann  on  a  patho- 
histological  basis,  are  as  follows  : — 

1.  Hyperemia  of  the  pulp. 

2.  Acute  superficial  pulpitis. 

3.  Acute  partial  pulpitis.  .      ,     » 

4.  Acute  total  pulpitis.  _  _      ^       ^^^^^^^  ^«™^- 

5.  Acute  partial  puruleut  pulpitis. 

6.  Acute  traumatic  puljiitis. 

7.  Chronic  parenchymatous  pulpitis.  1 

8.  Chronic  total  purulent  pulpitis.  j 

9.  Chronic  hypertrophic  granulomatous  pulpitis.    |     Chronic 

10.  Chronic  hypertrophic  sarcomatous  pulpitis.         |        forms. 

11.  Gangrene  of  the  pulp. 

12.  Idiopatliic  or  concretional  pulpitis.  J 

HYPEREMIA  OF  THE  PULP. 

In  this  disease  the  normal  sensitiveness  of  the  tooth  is 
increased  ;  that  is,  liot  and  cold  call  forth  a  slight  and 
ra])idly  disappearing  pain.  Hyperemia  occurs  mostly  in 
carious  or  worn  down  teeth,  and  is  due  to  thermic  irritants 


262  DISEASES  OF  THE  PULP. 

which  act  upon  the  insufficiently  covered  pulp,  or  (in 
caries)  to  injurious  bacterial  products.  Such  a  pulp  re- 
moved from  an  extracted  tooth  shows  under  slight  magni- 
fication dilatation  of  the  whole  vascular  system,  including 
both  the  afferent  as  well  as  the  efferent  vessels.  As  long  as 
circulation  continues  in  spite  of  this  dilatation  no  further 
disturbances  arise,  but  as  soon  as  it  ceases  inflammatory 
signs  appear. 

The  treatment  is  always  conservative,  that  is,  the  pulp 
should  be  encouraged  to  heal.  This  is  accomplished  by 
removal  of  the  causal  factors.  Exposed,  abraded  dentin 
must  be  protected  by  a  non-conducting  filling  material, 
and  in  order  to  stop  the  action  of  the  carious  products  as 
much  of  the  softened  dentin  must  be  removed  as  possible, 
and  the  cavity  closed.  The  latter  is  carried  out  in  the 
same  manner  as  in  the  case  of  caries  profunda,  being  sure 
to  introduce  a  non-irritant  and  non-conductive  material 
like  guttapercha  between  the  floor  of  the  cavity  and  the 
filling. 


ACUTE  SUPERHCIAL  PULPITIS. 

The  superficial  form  of  pulpitis,  which  has  also  been 
called  septic  inflammation  of  the  pulp  by  Arkovy,^  is  most 
frequently  seen  in  the  first  molars  of  young  patients,  in 
which  the  larger  portion  of  the  crown  has  been  destroyed 
by  caries  without  however  exposing  the  pulp  cavity,  Plate 
25,  Fig.  2.  In  this  type  of  pulpitis  an  unpleasant  sen- 
sation arises  spontaneously  which  sensitive  patients  call 
pain.  It  disappears  rapidly  but  recurs  after  short  inter- 
vals. The  use  of  the  excavator  as  well  as  irrigation  with 
cold  water  cause  little  or  no  pain. 

On  microscopic  examination,  we  find,  as  described  by 
Rothmann,  deposits  of  micro-organisms  "  like  finely  scat- 
tered sand  "  in  the  superficial  portion  of  the  pulp.  The 
pulp  tissue  itself  has  as  yet  suffered  no  alterations  what- 
ever. As  to  the  question  why  such  bacterial  invasions 
do  not  occur  in  other  carious  processes,  it  must  be  re- 
membered that  in  young  teeth  the  dentinal  tubules  are 


ACUTE  TRAUMATIC  PULPITIS.  263 

very  wide  and  easily  traversed  by  bacteria.  Furthermore, 
such  poorly  constructed  first  molars  possess  as  a  rule 
insufficient  vital  energy  to  build  a  protecting  transparent 
zone,  which  would  prevent  the  penetration  of  the  bacteria. 
The  therapy  is  satisfactory,  for  this  is  the  only  curable 
form  of  pulpitis.  In  my  experience,  the  best  results  are 
obtained  by  introducing,  for  from  five  to  ten  minutes,  in 
the  cavity  which  has  previously  been  thoroughly  cleaned, 
a  5  per  cent,  solution  of  formaldehyde  (that  is  5  per  cent, 
of  40  per  cent,  watery  solution)  or  a  crystal  of  pure  chlor- 
phenol.  After  a  number  of  the  bacteria  have  thus  been 
destroyed,  a  procedure  which  does  not  cause  the  pulp  the 
slightest  injury,  a  permanent  antiseptic  is  placed  on  the 
floor  of  the  cavity  before  introducing  the  filling.  For 
this  purpose  a  mixture  of  iodoform  and  creosote  is  used 
which  is  covered  with  an  asbestos  cap. 

ACUTE  PARTIAL,  TOTAL,  AND  TRAUMATIC  PULPITIS. 

If  any  portion  of  the  pulp  is  exposed  in  consequence 
of  a  carious  process,  or  through  an  injury  (Plate  25,  Fig. 
6)  all  the  symptoms  of  an  inflammatory  process  soon 
develop.  The  reddening  becomes  especially  noticea]:)le,  and 
von  Metnitz  has  even  observed  a  swelling  of  the  pulj)  in 
the  region  of  the  perforation. 

The  attacks  of  pain  in  iKirtial  pulpitis  vary  from  a  light 
to  a  severe  degree,  occur  at  frequent  intervals,  and  may 
arise  spontaneously,  or  after  irritation  from  taking  food 
or  cold  drinks.  The  patient  is  perfectly  able  to  indicate 
the  tooth  involved,  for  at  this  period  no  radiation  pains 
have  set  in.  Tapping  the  tooth  does  not  call  forth  pain, 
for  periosteal  involvement  is  absent. 

After  a  short  time  the  inflammatory  process  spreads  to 
the  remaining  pulp  tissue  so  that  an  acute  total  pulpitis 
develops  from  the  above  described  form.  It  is  diagnos- 
ticated by  the  following  subjective  and  objective  symptoms. 
The  pains  become  more  severe,  and  radiate  to  the  neigh- 
borliood  to  such  an  extent  that  they  can  no  longer  be 
traced  to  the  affected  tooth,  for  they  now  extend  throughout 


264  DISEASES  OF  THE  PULP. 

PLATE  25. 

Fig.  1. — Bicuspid  tooth  with  normal  healthy  pulp. 

Fig.  2. — Molar  with  acute  superficial  pulpitis.  Although  the  pulp 
cavity  has  not  been  penetrated,  yet  the  surface  of  the  pulp  which  lies 
nearest  to  the  focus  of  caries  is  reddened. 

Fig.  3. — Incisor  tooth  with  acute  partial  pulpitis.  At  the  seat  of 
perforation  of  the  pvilp  cavity  the  pulp  shows  circumscribed  redness. 

Fig.  4. — Molar  tooth  with  acute  total  pulpitis.  The  whole  pulp  is 
reddened. 

Fig.  5. — Bicuspid  tooth  with  partial  purulent  pulpitis.  The  crown 
of  the  pulp  is  partially  ulcerated,  and  is  therefore  yellow  in  color. 

Fig.  6. — Molar  tooth  with  traumatic  pulpitis.  A  fracture  of  the 
crown  exposed  the  pulp,  which  is  considerably  reddened. 

the  jaw  and  even  to  its  opposite  fellow.  Spraying  of  cold 
and  hot  water  cause  excruciating  pain,  and  a  similar  eifect 
follows  even  the  slightest  touch  of  the  pulp.  A  secondary 
periostitis  usually  develops,  so  that  tapping  the  tooth  or 
closing  the  mouth  causes  pain. 

Partial  inflammation  of  the  pulp  shows,  patho-anatom- 
ically,  a  circumscribed  reddening  which  extends  toward 
the  perforated  area  (Plate  25,  Fig.  3).  On  account  of 
the  associated  circulatory  disturbances,  the  afferent  vessels 
which  penetrate  the  root  canals  also  become  dilated,  and 
therefore  cause  a  reddening  in  that  region.  The  remaining 
pulp  tissue  remains  practically  normal.  The  pulp  tissue 
is  strongly  infiltrated ;  larger  and  larger  masses  of  mono- 
nuclear and  poly-nuclear  cells  arise  at  the  seat  of  the  pulp- 
cells,  and  in  the  region  of  the  nerves  and  blood-vessels. 
These  infiltrated  masses  unite  and  form  an  abscess  of  the 
pulp.  The  blood-vessels  are  dilated,  stasis  has  already 
developed  in  some  areas,  and  even  circumscribed  foci  of 
necrosis  are  seen  (Plate  28).  Acute  toted  jmlpitis  (Plate 
25,  Fig.  4)  shows  the  same  picture,  only  it  spreads  over 
the  whole  pulp. 

In  connection  with  the  treatment  we  must  bear  in  mind 
that  the  pulp  can  no  longer  be  saved,  and  should,  there- 
fore, be  devitalized  and  extirpated. 


rab.2S. 


Fig.l. 


Fig.  2. 


Fig.,3. 


Fig.  i 


Fig.S. 


Fig.  (j. 


CHRONIC  PARENCHYMATOUS  PULPITIS.        265 

ACUTE  PARTIAL  PURULENT  PULPITIS  AND  CHRONIC 
TOTAL  PURULENT  PULPITIS. 

(  Plate  25,  Fig.  5  and  Plate  26,  Fig.  4.  ) 

A  suppurating  inflammation  of  the  pulp  may  follow  an 
ordinary  acute  partial  pulpitis,  or  it  may  be  due  to  local- 
ized exposure  of  the  pulp.  The  process  leads  immediately 
to  a  loss  of  substance,  and  should,  therefore,  be  termed 
acute  ulcerative  pulpitis.  In  the  course  of  time,  that  is, 
when  the  process  becomes  chronic,  the  suppuration  involves 
a  greater  amount  of  the  pulp  tissue  and  forms  a  chronie 
total  'purulent  pndpitis.  The  true  suppurative  form  is  more 
likely  to  occur  when  the  pulp  cavity  is  not  exposed,  and 
especially  when  large  metallic  fillings  exist  ( see  Plate 
27,  Fig.  2 ).  The  pressure  and  erosion  due  to  the  pus 
causes  a  character  of  pain  in  such  teeth  which  is  altogether 
diiferent  from  that  experienced  in  non-suppurative  inflam- 
mations. The  pains  do  not  arise  suddenly,  but  are  very 
slight  at  the  beginning  and  increase  in  severity  gradually. 

They  are  characterized  usually  by  a  dull  gnawing  or 
throbbing  sensation.  Cold  water  causes  pain  only  in  the 
early  stages,  later  it  is  only  caused  by  hot  water.  Care- 
ful opening  of  the  pulp  cavity  during  which  some  of  the 
pus  is  discharged,  is  not  necessarily  painful  at  first,  but 
after  a  few  seconds  the  patient  complains  that  the  pain 
has  again  returned  to  the  diseased  tooth. 

The  treatment  is  the  same  as  in  the  case  of  the  ordinary 
partial  and  total  pulpitis.  The  only  difference  being  that 
the  surfiice  of  the  pulp  must  be  freed  of  pus  before  intro- 
ducing the  arsenic,  for  otherwise  tlie  pulp  will  be  devi- 
talized much  less  rapidly  and  accompanied  by  greater 
pain. 

CHRONIC  PARENCHYMATOUS   PULPITIS. 

(  Plate  26,  Fig.  6. ) 

This  form  of  pulpitis  is  described  by  Ark()vy  as  fol- 
lows :  "  The  microscopic  findings  show  that  the  pulp  is 
succulent,  swollen,  grayish  and    covered,  provided   the 


266  DISEASES  OF  THE  PULP. 

PLATE  26. 

Fig.  1. — Bicuspid  with  gangrene  of  the  pulp. 

Fig.  2. — Molar  with  chronic  hypertrophic  sarcomatous  pulpitis. 

Fig.  3. — Incisor  with  chronic  hypertrophic  granulomatous  pulpitis. 

Fig.  4.  Incisor  with  chronic  total  purulent  pulpitis.  The  yellow 
spots  indicate  the  abscess  cavities  in  the  destroyed  parenchyma. 

Fig.  5. — Bicuspid  with  ascending  pulpitis.  Pyorrhea  alveolaris 
caused  the  root  to  become  exposed  and  as  a  result  the  pulp  lying  at  the 
apical  foramen  became  infected. 

Fig.  6. — Wisdom  tooth  with  chronic  parenchymatous  pulpitis. 

whole  pulp  is  not  yet  involved,  with  snow-white  specks 
or  stripes,  while  in  other  cases  it  is  grayish  throughout 
and  very  transparent.  This  is  as  true  of  the  crown  as  of 
the  root  pulp.  The  exposed  coronal  portion  of  the  pulp 
shows  a  circumscribed  area  of  injection,  of  which  no 
traces  can  be  detected  in  the  neighboring  portions  of  the 
pulp. "  The  patient  experiences  no  sudden  spasms  of 
pain,  but  instead  a  continuous  discomfort  exists  which 
may  pass  into  a  tense  drawing  sensation.  Cold  water 
causes  a  painful  sensation  only  after  a  time.  Touching 
the  tooth  with  an  instrument  is  also  not  very  painful. 
Injuries  to  the  pulp,  on  account  of  general  dilatation  of 
the  blood-vessels,  lead  to  profuse  hemorrhages. 

Microscopically,  it  will  be  observed  that  the  pulp  cells 
have  multiplied  (hyperplasia)  and  that  the  blood-vessels 
are  congested  (hyperemia).  This  form  of  pulpitis  is  dis- 
tinguished from  chronic  total  pulpitis  by  the  smaller 
amount  of  leukocytic  infiltration.  The  pressure  caused  by 
the  hyperplasia  and  hyperemia  upon  the  elements  of  the 
pulp  for  weeks  and  months  finally  results  in  atrophy, 
(Plate  27,  Fig.  1).  Rothmann  writes  concerning  this 
condition  as  follows  :  "  The  originally  fibrous  adenoid 
tissue  of  the  pulp,  which  is  partially  composed  of  fine 
meshes,  is  completely  converted  into  a  widely  meshed 
adenoid  connective  tissue,  on  account  of  the  cell  prolifer- 
ation following  the  hyperemia. "  The  writer  cannot 
agree  with  this  view,  on  the  ground  that  the  full  grown 
pulp  possesses  no  adenoid  connective  tissue ;  that  is, 
reticular  tissue,  filled  with  leukocytes. 

In  the  rare  instances  in  which  a  periostitis  develops,  the 
treatment  consists  in  thorough  removal  of  the  pulp  tissue. 


Tab.26. 


QiD 


Iig.l. 


Eig.2. 


Fig/J. 


Fig.  4 


Fig. ,5. 


Fig.  a. 


CHRONIC  SARCOMATOUS  PULPITIS.  267 

CHRONIC  HYPERTROPHIC  GRANULOMATOUS  AND 
SARCOMATOUS  PULPITIS. 

We  have  illustrated  both  forms  on  Plate  26,  Figs.  2 
and  3.  They  differ  from  all  of  the  previously  described 
varieties  of  pulpitis  by  the  presence  of  true  growths. 
According  to  Arkovy,  some  are  simply  granulations 
(horaoplasia),  while  others  are  developed  from  degener- 
ated pulp  elements  (heteroplasia),  and  are  sarcomata. 

Chronic  hypertropkic  granulomatous  jndj^itis,  that  is, 
polyp  of  the  pulp  arising  from  granulation  tissue  ( Plate 
26,  Fig.  3),  represents  a  minimum  amount  of  new  growth 
which  rarely  exceeds  the  size  of  a  pea.  This  polyp  does 
not  cover  the  whole  surface  of  the  pulp,  but,  at  the  most, 
only  one  or  two  tips  of  that  structure.  The  consistency  is 
soft,  on  account  of  which  touching  it  with  an  instrument 
may  very  easily  cause  an  injury,  which  is  always  accom- 
panied by  a  rather  severe  hemorrhage. 

The  patients  usually  suffer  no  pain ;  only  mechanical 
insults  call  forth  a  sensation  similar  to  that  which  occurs 
when  an  inflamed  gum  is  irritated. 

Arkovy  classifies  under  the  head  of  chronic  hyper- 
trophic sarcomatous  pulpitis  all  those  neoplasms  of  the 
pulp  which  are  clearly  outlined,  which  have  a  smooth  or 
lobulated  surface,  and  which  are  accompanied  by  but  little 
hemorrhage.  They  do  not  involve  one  or  two  tips  of  the 
pulp,  but  occupy  its  whole  crown,  and  fill  a  more  or  less 
large  portion  of  the  carious  tooth  cavity  (see  Plate  26, 
Fig.  2).  The  subjective  symptoms  are  similar  to  those 
of  the  granulomatous  form. 

The  differential  diagnosis  consists  in  distinguishing  it 
from  hypertrophies  of  the  gum,  and  eventually  from 
tumorous  masses  Avhich  grow  upward  from  the  depths  of 
the  alveoli.  In  the  first  case  the  growth  may  be  pressed 
out  of  the  carious  cavity  by  means  of  guttapercha  or 
cotton,  and  in  case  of  periosteal  tumors,  the  root  canal  is 
demonstrably  increased  in  size,  a  condition  which  is  less 
likely  to  be  seen  in  the  presence  of  pulp  polyps.  Such 
polyps  are  removed  by  means  of  the  thermocautery  or 


268  DISEASES  OF  THE  PULP. 


PLATE   27. 

Fig.  1. — Incisor  tooth  with  atrophy  of  the  pulp.  It  is  probable  that  a 
chronic  parenchymatous  pulpitis  formerly  existed  for  it  may  occasionally 
lead  to  an  atrophy. 

Fig.  2. — Bicuspid  tooth  with  a  chronic  total  purulent  pulpitis  which 
developed  underneath  a  large  metallic  filling. 

Fig.  3. — Incisor  tooth  with  idiopathic  or  concretional  pulpitis.  The 
pale  concretions  are  seen  as  points  in  the  somewhat  reddened  pulp. 

Fig.  4. — Molar  tooth  with  ascending  gangrene  of  the  pulp. 

the  lancet,  and   the   remaining  pulp  tissue  destroyed  and 
extirpated. 

GANGRENE  OF  THE  PULP. 

(Plate  26,  Fig.  1.) 

Gangrene  of  the  pulp  may  follow  as  a  sequel  to  most 
of  the  previously  described  acute  and  chronic  inflamma- 
tions of  the  pulp,  or  this  structure  may  undergo  gangren- 
ous degeneration  without  having  been  preceded  by  any 
symptoms  of  disease.  It  occurs  most  frequently  in  teeth 
which  have  been  badly  necrosed.  The  reason  why  gan- 
grene should  develop  instead  of  suppuration,  is  probably 
explained  by  the  presence  of  different  microorganisms. 
Thus  in  purulent  pulpitis  pyogenic  bacteria  predominate, 
and  in  gangrenous  pulpitis  true  excitants  of  putrefaction 
exist.  Arkovy  obtained  such  a  microorganism  in  pure 
culture  from  a  large  number  of  gangrenous  pulps,  and  the 
writer  has  also  isolated  it.  That  this  organism,  called  the 
bacillus  gangi-ence  pulpcE,  is  really  able  to  cause  a  typical 
gangrene  of  the  pulp  has  been  determined  by  Arkovy, 
through  inoculation  of  healthy  teeth. 

The  development  of  gangrene  destroys  the  pulp  not 
only  when  the  pnlp  cavity  has  been  opened,  but  also 
rarely  in  intact  teeth,  and  more  frequently  in  teeth  sup- 
plied with  large  fillings.  In  very  rare  cases  on  opening 
of  the  tips  of  the  roots,  an  ascending  form  of  gangrene, 
may  be  observed  following  pyorrhea,  Plate  27,  Fig.  4. 
This  condition  is  easily  explained,  for  injurious  bacteria 
enter  the  pulp  through  the  apical  foramen,  while  gangrene 
of  intact  teeth  is  explained  by  the  fact  that  microorganisms 


Tab. 2  7. 


Fig.l. 


Fiff.Ji 


b'icj.. 


Fig.  4 


IDIOPATHIC  OR   COXCRETIONAL  PULPITIS.      269 

circulate  in  the  healthy  pulp  as  they  do  in  healthy  tissues 
in  other  portions  of  the  body. 

When  a  tooth  which  is  diseased  in  this  manner  is 
opened,  the  foul  odor  is  tiie  first  characteristic  noted.  A 
pledget  of  cotton  inserted  into  the  cavity  will  bring  forth 
a  dirty  colored  discharge,  instead  of  the  red  discharge 
seen  in  most  forms  of  pulpitis,  or  the  yellow  discharge  of 
the  suppurative  form.  In  the  early  stages,  sounding  the 
deeper  portions  with  an  explorer  still  causes  pain.  Later 
all  sensitiveness  ceases  and  the  whole  root  caual  is  filled 
with  this  foul  mass.  In  this  stage  the  whole  tooth  assumes 
a  dark  color. 

The  pains  are  considerable  and  occur  in  paroxysmal 
attacks,  and  at  the  beginning  are  easily  mistaken  for 
those  of  acute  partial  and  total  pulpitis.  They  differ, 
however,  from  these  inasmuch  as  they  react  less  promptly 
to  mechanical  irritants,  and  are  also  not  as  prompt  in  re- 
acting to  heat  and  cold.  In  the  case  of  unopened  pulp 
cavities,  on  the  contrary,  and  when  the  pulp  tissue  has 
already  undergone  extensive  destruction,  considerable  pain 
is  caused  by  the  action  of  warm  water.  The  explanation 
of  this  is  that  the  gas  evolved  from  the  putrefactive 
changes  is  locked  in  the  pulp  cavity,  and,  expanding  on 
account  of  the  higher  temperature,  exerts  pressure  upon 
the  surviviug  nerve  elements,  or  upon  the  periosteum. 
The  periosteum  becomes  rapidly  involved,  and  as  a  result 
the  tooth  is  highly  sensitive  whenever  an  attempt  is 
made  to  masticate,  or  whenever  the  tooth  suffers  any 
external  disturbance. 

The  treatment  requires  especial  discussion  and  will 
therefore  be  considered  in  the  next  chapter. 

IDIOPATHIC  OR  CONCRETIONAL  PULPITIS. 
(Plate  27,  Fig.  3). 

The  development  of  dentinal  tumors  in  the  body  of  the 
pulp,  or  the  deposition  of  concretions  of  lime,  may  cause 
such  severe  pain  as  to  compel  the  patient  to  consult  us. 
Perfectly  healthy  teeth  may  develop  this  condition,  but 


270  DISEASES  OF  THE  PULP. 

PLATE  28. 
Acute  partial  pulpitis. 

a.  Normal  pulp  tissue. 
h.  Dilated  blood-vessels. 

c.  Blood-vessels  filled  with  coagulated  blood. 

d.  Eound  cell  infiltration. 

e.  A  necrotic  and  caseous  focus. 
Longitudinal  section.     Hematoxyl. — Eosin. 

PLATE   29. 
Clironic  pulpitis. 

a.  Normal  pulp  tissue. 
6.  Dilated  blood-vessels. 
c.  Leukocytic  infiltration. 
Longitudinal  section.    Hematoxyl. — Eosin. 

PLATE   30. 

Abscess  of  the  Pulp. 

a.  Normal  tissue. 
6.  Odontoblastic  layer. 
c.  Abscess  cavity. 
Longitudinal  section.     Carmin. 

PLATE  31. 
Fatty  degeneration. 

o.  Normal  pulp  tissue. 

6.  Blood-vessel  cut  transversely,  filled  with  red  blood  corpuscles. 

c.  Fat  cells ;   the  nuclei  are  compressed  against  the  surrounding 

capsule. 
Longitudinal    section.     High   magnification.     Picrin-Formol.     Hema- 

toxyl-Eosin. 

PLATE   32. 

Reticular  atrophy  caused  by  hydremic    degeneration  of  the  pulp 
elements. 
a.  Normal  pulp  tissue. 
h.  Odontoblastic  layer. 

c.  Cells  which  have  undergone  hydremic  degeneration  still  showing 
some  of  the  nuclei  at  the  walls. 

it  occurs  more  often  when  a  considerable  portion  of  the 
crown  has  been  worn  down. 

The  pains  are  usually  neuralgic  in  character,  and  the 
condition  may,  therefore,  be  easily  mistaken  for  trigeminal 
neuralgia.  Inasmuch  as  the  patient  cannot  always  tell 
which  tooth  is  affected,  and  as  the  objective  diagnosis  is 
not  always  possible,  it  may  be  necessary  to  sacrifice  several 
teeth  before  the  diseased  one  is  located.  Extraction  is  of 
course  of  value,  yet  it  is  not  the  only  therapeutic  remedy 


Tab.2S. 


■■/■■■  '^(-f-S^ 


.;j3 
■•.  .•'„  .* 
:■•:  7.  a 


v^®;-;;::^ 


,:]^}^':0I 


mm 


d  -  - 


Tab.:^ff. 


1 


BVISr-.-  ..•  -.    .x",',rtV  -.     •       '>".i 


Tab.  30. 


^  mmw 


— b 


■-•:i\3 


Tab.37. 


Tab.  32. 


1  %'•" 


CONCERNING  DISEASES  OF  THE  PULP.         271 

in  this  condition.  The  same  object  may  be  obtained  by 
extirpation  of  the  pulp,  provided  this  is  not  made  impos- 
sible by  too  extensive  involvement  with  concretional 
deposits.  This  should  always  be  attempted  before  extrac- 
tion is  resorted  to, 

PATHOLOGIC     AND     ANATOMIC     REMARKS 
CONCERNING  DISEASES  OF  THE  PULP. 

Pulp  tissue  differs  considerably,  pathologically,  from 
other  similar  tissues  of  the  animal  organism.  This  dif- 
ference manifests  itself  chiefly  by  the  astonishing  lack  of 
resistive  power  to  disease.  A  restitution  of  healthy  tissue 
in  place  of  that  which  has  been  destroyed  has  not  as  yet 
been  observed,  even  though  the  only  case  in  the  literature 
(by  Gysi)  seems  to  contradict  that  statement.  The  author 
has  also  failed,  in  the  microscopic  examination  of  many 
hundred  pulps,  to  observe  any  but  a  very  slight  tendency 
to  the  development  of  scar  tissue. 

In  our  opinion,  the  reason  for  this  poor  healing  capacity 
of  the  pulp  can  be  traced  to  the  narrow  afferent  and  effer- 
ent vessels,  together  with  the  poor  supply  of  lymph 
spaces.  Even  a  circumscribed  disease  of  the  pulp  leads 
to  local  circulatory  disturbances,  which  are  naturally 
shared  by  the  vessels  enclosed  within  the  root  canal.  In 
that  case,  the  blood-vessels  of  the  root  pulp  are  also  con- 
gested, and  show  a  highly  red  color.  The  increased  pres- 
sure thus  formed  interferes  with  the  outflow  of  the  blood, 
as  well  as  its  circulation  throughout  the  plexus  within  the 
pulp.  Such  a  disturl)ance  occurs  also  in  other  organs,  but 
is  more  or  less  completely  compensated  for  by  collateral 
circulation.  The  insufficient  anastomosis  of  the  blood 
vessels,  which  is  necessary  because  of  the  narrow  canal 
with  rigid  walls  in  which  they  are  enclosed,  explains  per- 
fectly the  astonishing  lack  of  resistance  of  the  pulp. 

Aside  from  the  few  cases  of  tumor  formation,  prac- 
tically only  degenerative  processes  occur,  which  because 
of  their  pathologic  anatomy  are  termed  regressive  disturb- 
ances m  nutrition.      As  demonstrating  these  changes  the 


272         CONGERNINO  DISEASES  OF  THE  PULP. 

following  specimens  are  shown.  On  Plate  28  is  seen  a 
longitudinal  section  of  a  chronically  inflamed  pulp,  stained 
with  hematoxylin-eosin,  in  which  one  may  study  the  pic- 
ture of  a  circumscribed  necrosis.  Some  areas  show  infil- 
tration of  round  cells ;  the  blood-vessels  are  dilated  and 
their  lumina  are  partially  occluded  with  blood  clot.  The 
necrotic  area  is  soft  in  consistency,  and,  because  of  its  nu- 
cleated character,  is  similar  to  the  caseating  focus  which 
tends  to  develop  in  richly  cellular  tissue  as  a  result  of 
tuberculous  disease.  Accordingly,  this  is  a  case  of  begin- 
ning caseation,  which  would  probably  have  proceded  to 
necrosis  of  the  whole  pulp  tissue,  provided  the  pulp  had 
not  been  extirpated. 

Plate  29  shows  a  chronically  inflamed  pulp  with  enor- 
mous dilatation  of  the  blood-vessels.  This  dilatation  of 
the  arteries  and  veins  brings  many  cross-sections  of  ves- 
sels into  view  which  were  previously  invisible,  and  thus 
gives  the  impression  that  a  large  number  of  new  vessels 
have  been  formed.  The  tissue  in  the  neighborhood  of 
these  dilated  vessels  is  considerably  infiltrated.  The  fact 
that  individual  vessels,  situated  in  normal  areas,  are  also 
dilated  may  be  accepted  as  an  indication  of  the  manner 
in  which  local  circulatory  disturbances  may  interfere  with 
the  circulation  of  the  blood  throughout  the  whole 
pulp. 

Plate  30  shows  an  abscess  following  a  total  purulent 
pulpitis.  The  true  abscess  cavities,  which  are  still  par- 
tially filled  with  pus,  possess  no  distinct  boundary,  but  pass 
into  spaces  which  developed  from  total  destruction  of 
certain  portions  of  the  pulp.  This  destructive  process 
tends  to  spread  in  the  walls  of  the  cavities,  as  may  be  seen 
by  the  cellular  disintegration  of  the  same. 

Plate  31  shows,  under  hiarh  magnification,  a  section  fixed 
with  picrin-formol,  and  stained  with  lieraatoxylin-eosin. 
The  pulp  tissue  is  normal,  excepting  for  the  presence  of 
swollen  yellow  cells  with  nuclei  situated  at  the  walls. 
Eventually  a /af^y  degeneration  may  develop,  for  the  cells 
appear  exactly  like  fat  cells  of  a  fatty  heart.  The  prepa- 
ration is  from  a  young  individual.      The  pulp  was  not 


IDIOPATHIC  OR   CONCRETIONAL  PULPITIS.     273 

inflamed,  but  was  removed  from  the  tooth  for  other  reasons, 
and  the  discovery  was  therefore  accidental. 

Plate  32  shows  the  pretty  picture  of  a  reticular  atropliy 
which  developed  from  a  hydremic  degeneration  of  the  pulp 
tissue.  In  certain  areas  one  may  still  see  cells  filled  with 
fluid,  the  membi'anes  of  which  are  distended  like  blad- 
ders, and  whose  nuclei  are  pressed  against  the  walls.  In 
other  areas  these  cells  form  vacuoles  by  fusion.  This 
hydremic  degeneration  spreads  to  the  root  portion  of  the 
pul]),  and  gives  it  a  spongy  appearance.  The  crown  por- 
tion, which  is  not  shown  here,  has  been  altered  by  inflam- 
mation. 

Plate  33  shows  two  large  free  lime  concretions  which 
have  almost  completely  compressed  the  pulp  tissue. 
These  oval  lime-bodies,  the  layers  of  which  are  concen- 
trically arranged,  caused  an  idiopathic  pulpitis  and  led  to 
the  extraction  of  the  involved  tooth. 

Plate  34  shows  another  variety  of  lime-bodies,  which 
are  found  in  a  pulp  associated  with  a  partial  pulpitis. 
The  preparation  shows  an  area  of  normal  pulp  tissue 
in  which  are  seen  a  considerable  number  of  compara- 
tively small  lime-bodies  which  are  arranged  in  layers. 
The  dark  color  of  these  bodies  which  is  obtained  on  stain- 
ing hematoxylon  indicates  that  deposits  are  concerned 
which  are  at  present  undergoing  calcification,  for,  as  a  rule, 
old  concretions  do  not  color  so  intensely. 

Plate  35  shows  calcium  r/rannles.  These  are  more  likely 
to  develop  in  the  connective  tissue  around  the  blood- 
vessels, which  has  undergone  hyaline  changes.  In  fact 
this  picture  shows  a  calcium  granule  which  rests  upon  a 
blood-vessel,  and  which  seems  to  compress  it  to  one  side. 

Plate  36  shows,  witli  high  power,  a  chronic  inflammatory 
process,  which  has  degenerated  the  pulp  to  such  an  extent 
that  it  does  not  look  unlike  a  psammoma  of  the  dura  mater. 
The  whole  tissue  consists  only  of  fibrous  strands  M'ith  a 
few  normal  pulp  cells.  All  the  remaining  pulp  cells,  and, 
as  far  as  can  lie  seen,  the  majority  of  the  vessels  have 
undergone  hyaline  degeneration.  These  tissues  have  been 
changed    into  round  or  polygonal  hyaline  bodies,  whose 

18 


274         CONCERNING  DISEASES  OF  THE  PULP. 

PLATE  33. 

Large  concretions  of  lime  which  have  a  layer  formation  like  that  of 

an  onion. 

a.    Normal  pulpitis. 
6.     Lime  granules. 
Longitudinal  section.     Hematoxyl.-Eosin. 

PLATE   34. 
Small  Concretions  of  Lime. 

a.     Normal  pulp  tissue. 
6.     Blood-vessels. 

f.    Small   concretion  of  lime  wliicli  is  also  arranged  in  concentric 
layers  like  an  onion. 

Longitudinal  section.     Hematoxyl.-Eosin. 

PLATE   35. 
Deposits  of  Lime. 

a,  Normal  pulp  tissue. 

6.  Blood-vessel  (longitudinal  section). 

c.  Blood-vessel  (cross  section). 

d.  Deposits  of  lime,  of  which  the  upper  one  rests  upon  a  blood- 
vessel. 

Longitudinal  section.     Hematoxyl.-Eosin. 

PLATE  36. 

Hyaline  Degeneration  of  the  Pulp. 

a.     Fibrillary  connective  tissue. 
6.     Blood-vessels. 

c.     Hyaline  flakes  VFithin  which  beginning  calcification  is  shown. 
Longitudinal  section.     Hematoxyl.-Eosin.     High  magnification. 

PLATE  37. 
A  senile  sclerotic  pulp. 

a.  Fibrillary  connective  tissue  poor  in  nuclei. 

b.  A  longitudinal  section  of  a  blood-vessel. 


centers  are  calcified,  and  therefore  stain  blue  with  hema- 
toxylin. The  periphery  of  each  body,  however,  appears 
as  a  transparent,  pale,  and  colorless  hyaline  halo. 

All  of  the  pulps  thus  far  described  were  obtained  from 
young  persons  in  order  to  exclude  senile  changes. 

Plate  37  shows  a  senile  pulp  in  which  the  usually  soft, 
richly  cellular  pulp  tissue  is  substituted  by  a  firm,  fibrous 
connective  tissue  which  has  but  few  nuclei.  The  change 
is  therefore  a  sclerosis.     The  long  extent  of  the  course  of 


Tab.  33. 


Tab.S^. 


ih', 


-'-ikS'i 


.'•■  ■•■all  ,.:     :  v;^     .  5.i, 


V 


^— * 


Tab.  Jo. 


1 1,1  ,1    J, 


u---.^^-J-^-  d 


.r. 


G^ 


lab.  J  6. 


rab.-37. 


b  — 


DIAGNOSIS  OF  PULP  DISEASES.  275 

these  fibrillffi  of  the  connective  tissue  is  remarkable,  as 
well  as  the  long  course  of  the  blood-vessels,  which  is  due 
to  the  former  condition. 

These  pathohistological  examples  are  presented  in  order 
to  demonstrate  the  course  of  the  diseases  of  the  pulp. 

DIAGNOSIS  OF  PULP  DISEASES. 

Arkovy  has  attempted,  in  an  exhaustive  and  classical 
work,  to  establish  the  diagnosis  from  the  objective  examina- 
tion as  well  as  from  the  anamnesis.  Even  though  his 
advice  is  closely  followed  it  is  not  always  possible  to 
obtain  a  correct  impression  of  the  existing  disease  of  the 
pulp.  This  is  accounted  for  by  the  fact  that  patients,  as 
well  as  the  sensitiveness  of  pulps,  vary  considerably. 
Furthermore  the  symptom-complex  may  alter  in  a  very 
short  time,  and  with  it  the  reactions.  The  thermometer  of 
Walkhofis  recommended  when  it  is  only  desired  to  deter- 
mine the  presence  of  pulpitis,  without  deciding  its  exact 
nature,  which  is  frequently  sufficient  for  clinical  purposes. 
Walkhoif  has  called  attention  to  the  fact  that  water  at 
37°  C  never  causes  the  teeth  any  pain,  but  that  changes  of 
a  slight  degree  in  temperature  either  alDove  or  below  37°  C. 
causes  pain  when  the  dentin  is  sensitive,  and  more  intense 
pain  when  pulpitis  exists.  That  investigator  constructed 
a  syringe,  which  is  so  arranged  that  the  temperature  of  the 
water  may  be  read  off  directly  from  a  thermometer  inserted 
in  its  piston.  Thus,  if  a  tooth  becomes  painful  when  it  is 
s})rayed  with  either  cold  or  hot  water,  a  conclusion  may 
be  formed  as  to  the  condition  of  the  pulp  ;  but  here,  too,  we 
must  not  disregard  the  fact  that  the  varying  sensitiveness 
of  patients  makes  the  diagnosis  difficult.  As  a  rule,  then, 
the  diay)iosis  of  pulpitis  may  be  made  when  either  cold  or 
warm  water  gives  the  tooth  pain.  If  pain  is  caused  only 
by  warm  water,  and  not  by  cold  water,  it  may  be  safely 
assumed  that  a  considerable  lesion  of  the  tissue  already 
exists  ;  that  is,  the  pulp  has  been  partially  or  wholly 
destroyed  by  a  suppurative  or  gangrenous  process. 

The  writer  has  observed  that  indolent  pulps  fail  to  react 


276      TREATMENT  OF  DISEASES  OF  THE  PULP. 

to  thermic  stimuli,  and  has,  therefore,  sought  for  another 
method,  in  the  employment  of  a  chemical  irritant.  This 
consists  in  removing  as  carefully  as  possible  the  carious 
mass,  and  then  applying  for  several  minutes  a  5  per  cent, 
(of  the  40  per  cent,  strength)  solution  of  formaldehyd 
to  the  cavity  which  has  been  protected  against  moisture. 
Usually  a  slight  drawing  pain  develops,  which  disappears 
after  a  short  time.  If,  on  the  contrary,  the  pain  under 
these  circumstances  continually  increases  in  severity,  it 
may  be  safely  concluded  that  an  inflammation  of  the  pulp 
exists,  which  has  been  aroused  through  the  influence  of 
the  irritation  caused  by  the  formaldehyd. 

Our  attempts  to  find  a  wholly  satisfactory  explanation 
of  the  formaldehyd  reaction  have  as  yet  been  in  vain. 
Until  more  positive  information  can  be  offered  it  suffices 
to  assume  that  this  irritating  agent  passes  more  rapidly 
to  the  pulp  because  the  odontoblastic  processes  (Tomes' 
fibers)  are  either  altered  or  have  disappeared  from  the 
dentinal  canals.  When  the  pulp  is  perfectly  intact  the 
contents  of  the  dentinal  canals  are  also  intact,  and  there 
develops  in  them  through  the  action  of  the  formaldehyd 
a  peculiar  coagulum,  which  prevents  the  formaldehyd  from 
penetrating  further. 

TREATMENT  OF  DISEASES  OF  THE  PULP. 

THE  APPLICATION  OF  A  CAP  TO  THE  PULP. 

When  the  pulp  has  been  exposed  by  any  process,  and  is 
not  inflamed,  it  may  be  bridged  over  with  some  non- 
irritating  material.  Care  must  be  taken  to  select  a  pro- 
tecting material  which  is  easily  sterilized.  It  must  also 
be  chemically  indifferent  and  be  a  poor  conductor  of  heat. 
A  cap  made  of  asbestos  Mdiich  can  be  heated  probably 
fulfils  these  requirements  the  best.  This  cap  is  placed 
over  the  pulp  in  such  a  manner  that  the  latter  will  not  be 
touched,  and  is  then  covered  with  a  thin  layer  of  cement, 
but  without  exerting  any  pressure. 

A  pulp  covered  in  this  manner  is  believed  to  protect 
itself  from  foreign  bodies  by  developing  secondary  dentin, 


THE  DESTRUCTION  OF  THE  PULP.  277 

and  thus  reestablishing  normal  conditions.  In  spite  of 
this  treatment,  although  we  do  not  understand  the  exact 
cause,  the  pulp  occasionally  becomes  inflamed  in  the 
course  of  time.  Therefore,  it  is  advisable  not  to  perma- 
nently fill  the  over-capped  tooth  immediately,  but  to  wait 
several  weeks  or  months. 

If  the  exposed  pulp  should  bleed,  AValkhofF advises  that 
it  be  touched  with  a  concentrated  solution  of  chlorphenol, 
and  then  apply  an  iodoform  paste.  The  writer  has  made 
tests  with  small  amounts  offonnaldehyd-c/elatin,  and  found 
that  it  has  a  good  eifect  upon  the  pulp.  It  is  probable  that 
portions  of  the  remaining  living  pulp  tissue  absorb  this 
material,  and  the  formaldehyd  being  set  free  exerts  a 
strong  disinfectant  action.  We  cannot  explain  why  this 
antiseptic,  usually  so  strongly  irritating,  is  non-irritant  in 
tlie  form  of  formaldeliyd-gelatin  ;  it  may  be  due  to  the 
fact  that  in  the  latter  form  only  minute  amounts  are 
liberated. 

THE  DESTRUCTION  AND  EXTIRPATION  OF 
THE  PULP. 

If  it  is  decided  to  remove  an  inflamed  pulp  partially 
or  completely,  which  is  frecpiently  the  only  possible  treat- 
ment, a  certain  amount  of  preparation  is  necessary,'  for 
w^ithout  it  this  operation  would  be  too  painful.  There- 
fore it  must  be  previously  cauterized.  This  is  accom- 
plished with  arsenic  or  with  arsenious  acid,  which  was 
introduced  by  Spooner  in  1836.  In  more  recent  times 
Dal  ma  recommended  an  alkaloid,  nervocidin,  which  will 
probably  play  an  important  role  in  dental  therapy,  even 
though  in  our  experience  it  has  been  less  reliable  than 
arsenic.  Arkovy,  Detzner,  and  others  claim  that  arsenic 
causes  at  first  a  hyperemia  of  tlie  blood-vessels,  M'hich  is 
followed  by  circulatory  distur])ances  with  capillary  stasis. 
After  a  few  hours  the  nerves  lose  their  physiologic  func- 
tion. This  is  not,  however,  accompanied  by  coagulation 
of  the  pulp  tissue  ;  on  the  contrary,  this  tissue  remains 
soft  and  capable  of  absorbing  substances.  The  arsenic  is 
so  rapidly  absorbed  that,  as  personal  tests  have  shown,  in 


278      TBEATMENt  OF  DISEASES  OF  THE  PULP. 

the  pulp  which  has  been  cautei'ized  but  a  short  time 
previously  no  trace  of  the  arsenious  acid  can  be  detected. 
Ai'senic  is  best  employed  in  the  form  of  a  paste,  of 
which  a  quantity  the  size  of  the  head  of  a  pin  is  placed 
into  the  cavity,  from  which  the  softened  mass  has  been 
reraov^ed  without  exerting  pressure  upon  the  pulp.  In 
order  to  prevent  cauterization  of  the  oral  mucous  mem- 
brane, the  cavity  must  be  well  closed  by  means  of  a 
guttapercha  or  cement  filling.  Of  a  number  of  remedies 
employed  to  counteract  the  painful  hyperemia,  which 
develops  at  the  beginning  of  the  cauterization,  tannin  is 
probably  the  best.  This  is  true  not  only  because  it  has 
an  astringent  action  and  is  therefore  pain  alleviating,  but 
also  because  it  gives  the  pulp  a  firm  consistency  which 
makes  the  extirpation  much  less  difficult.  The  following 
mixture  is  most  useful : 

Acidi  arsenicos, 

Creosoti,  da  3ji  (5.0). 

To  a  pledget  of  cotton  moistened  with  this  fluid  a  little 
tannic  acid  is  added,  and  the  whole  is  then  introduced  into 
the  cavity  in  such  a  manner,  that  the  tannin  lies  directly 
over  the  pulp. 

In  very  desperate  cases,  the  method  recommended  by 
Walkhoif  is  of  service.  He  applies,  depending  upon  the 
severity  of  the  case,  either  for  a  few  minutes  or  from  one 
to  two  days,  a  concentrated  solution  of  chlorphenol ;  after 
this  procedure,  the  introduction  of  arsenic  never  causes 
pain.  The  majority  of  authorities  permit  the  arsenic 
to  remain  in  the  tooth  only  from  one  to  two  days,  after 
which  period  of  time,  however,  the  pulp  can  only  rarely 
be  removed  without  causing  some  pain.  If  the  arsenic  is 
removed,  say  in  forty-eight  hours,  and  the  tooth  tempora- 
rily closed  and  allowed  to  rest  for  three  or  four  days, 
the  pulp  commences  to  slough,  when  it  is  possible  to 
extract  even  the  root-portion  without  causing  any  pain. 

For  the  removal  of  the  pulp  in  the  root-canals,  a  finely- 
barbed  brooch  (Fig.  134)  is  introduced,  turned  around  on 
its  longitudinal  axis,  and  then  drawn  out.     The  whole 


THE  DESTRUCTION  OF  THE  PULP.  279 

pulp  will  cling  in  the  form  of  brownish-red,  tough  fibres, 
to  the  instrument,  provided  the  pulp  tissue  has  not  under- 
gone decomposition,  and  if  the  tannin  had  sufficient  time 
to  act  thoroughly. 

In  that  case — that  is,  when  the  pulp  is  not  destroyed — it 
mav  be  assumed,  since  the  instrument  employed  had  been 
sterilized,  that  the  root  canal  is  not  septic,  and  it  may, 
therefore,  be  immediately  filled  without  further  prelimi- 
nary treatment. 

The  material  for  filling  a  root  canal  requires  no  anti- 
septic action,  and  can  therefore  be  selected  according 
to  preference.  Guttapercha,  which  is  preferred,  is  forced 
into  the  canal  in  the  form  of  fine  points,  or  it  is  pumped 
into  that  part  of  the  tooth  in  a  liquid  state  (chloroform 
solution).  Many  operators  introduce  fine  metallic  points 
coated  with  cement,  which  are  so  inserted  into  the  canal 
that  a  short  end  rises  up  into  the  pulp  cavity.  Metallic 
})ins  are  to  be  preferred  to  other  materials,  because  they 
can  be  heated  and  thus  sterilized,  and  because  they 
can  be  easily  passed  to  the  tip  of  the  canal.  A  metallic 
pin  is  furthermore  of  advantage,  when  eventually  a 
recurring  periostitis  develops,  because  it  can  be  grasped  by 
its  protruding  end  and  easily  worked  loose  from  the  root. 


Fig    134.— Brooch  for  cleansing  a  root  canal. 

It  is  understood,  of  course,  that  before  introducing 
a  root  filling,  the  canal  must  be  absolutely  clean  and 
dry.  In  order  to  thoroughly  cleanse  a  root  canal,  it 
suffices  to  wipe  it  repeatedly  with  an  instrument  wrapped 
with  cotton  which  has  been  immersed  in  ether  or 
chloroform.  Such  an  instrument  is  illustrated  in  Fig. 
lo4.  After  this  procedure,  the  canal  is  thoroughly  dried 
with  warm  air. 

If  the  i>ulp  has  been  destroyed  by  extensive  c/angrenous 
or  putrefactive  processes  and  no  longer  hangs  together,  its 
extraction    will   be   much   more   difficult,   because   only 


280      TREATMENT  OF  DISEASES  OF  THE  PULP. 

PLATE   38. 

Demonstration  of  the  amputation  of  the  pulp  on  a  longitudinally- 
cut  molar. 

Fig.  1. — Focus  of  caries  reacbiug  to  the  pulp.     The  latter  is  partially 
inflamed  and  was  cauterized  with  arsenic. 

Fig.  2.^The  carious  cavity  is  prepared  for  the  reception  of  a  filling, 
and  the  crown  pulp  has  been  drilled  away. 

Fig.  3. — A  cotton  swab   soaked   in  creosote  lies  at  (a)  in  the  pulp 
cavity,  which  at  (6)  is  protected  and  supported  by  collodium  and  cotton. 

Fig.  4. — An  antiseptic  lies  at  (a)  over  the  stump  of  the  pulp  ;  at  (6) 
is  a  pellet  of  tinfoil ;   and  at  (c)  the  completed  metallic  filling. 

single  shreds  can  be  removed  with  the  brooch  at  one 
time.  During  this  manipulation,  great  care  must  be 
exercised  lest  septic  portions  of  the  pulp  be  forced  out  of 
the  apical  foramen,  for  in  that  manner  a  severe  type 
of  periostitis  may  be  caused.  The  work  must,  therefore, 
be  careful  and  geatle. 


Fig.  135.— Brooch  wrapped  with  cotton  for  sterilization  and  desiccation 
of  the  root  canals. 

If  the  brooch  meets  an  obstruction,  an  atresia  of  the 
root  canal  exists,  which  may  sometimes  be  of  so  great 
a  degree  that  the  lumen  is  completely  locked  or  displaced 
because  of  concretions  of  lime.  This  condition  may  also 
be  caused  by  curvature  of  the  roots.  In  such  cases  an 
increase  in  the  caliber  of  the  canal  should  be  made  with  a 
drill.  Since,  however,  the  drill  driven  by  the  machine 
does  not  always  follow  the  canal,  but,  on  the  contrary, 
tends  to  establish  a  false  course,  especially  when  the  root 
is  crooked,  it  may  perforate  the  side  of  the  root.  Further- 
more, since  the  drill  frequently  breaks  off  and  remains  fast 
in  the  root,  we  should  explore  frequently  ahead  of  the 
drill,  and,  in  doubtful  cases,  we  should  resort  to  other 
means  of  increasing  the  size  of  the  canal.  This  consists 
in  the  employment  of  acids  (sulphimo  acid,  Callahan  ; 
nitro-hydrocUoric  acid,  Boennecken),  by  means  of  which  a 
superficial  decalcification  of  the  canal  walls,  and,  therefore, 
a  dilation  of  the  lumen  is  obtained.     In  order  to  prevent 


Tab.JS. 


Eig.l. 


Eig.. 


Fig.3. 


Fig.  4,. 


AMPUTATION  OF  THE  PULP.  281 

too  extensive  destruction  of  the  tissue,  the  concentrated 
solutions  should  be  allowed  to  act  but  a  few  minutes, 
after  which  it  should  be  neutrahzed  with  sodium 
bicarbonate. 

The  application  of  acids  does  not  only  assure  an 
increase  in  the  size  of  the  canal,  but  a  sterilization  at  the 
same  time.  This,  however,  does  not  suffice  for  the 
immediate  filling  of  the  root  canal,  for  it  is  still  necessary 
to  introduce  an  antiseptic  dressing  into  the  root  before 
filling.  These  antiseptic  applications  must  be  continued 
for  a  longer  or  shorter  period  of  time,  depending  upon 
the  degree  of  destruction  of  the  pulp  and  upon  the 
presence  or  absence  of  periostitis. 

When  the  pulp  has  been  destroyed,  a  filling  material, 
which  has  an  antiseptic  action,  should  be  used  for  the 
root  canals.  There  is  nothing  better  for  this  purpose 
tlian  a  paste  of  iodoform  and  creosote,  but  as  cotton 
is  rapidly  destroyed,  fine  silk  fibers  is  better  as  a  vehicle  for 
this  antiseptic.  Silk  slides  much  better  into  the  canal 
than  cotton,  and  when  necessary  is  easily  withdrawn. 

AMPUTATION  OF  THE  PULP. 

All  pulp  tissue  cannot  be  removed  from  certain  teeth, 
especially  from  teeth  possessing  a  multiple  number  of 
roots,  as  is  explained  in  connection  with  metallic  cor- 
rosions on  pages  38  and  39. 

In  order  to  avoid  the  cleansing  of  inaccessible  canals, 
Witzel  devised  a  method  which  he  called  amputation  of 
the  pulp.  It  consists  in  drilling  away  the  previously 
devitalized  crown  pulp  and  placing  a  permanent  antiseptic 
upon  the  stumps  of  the  root  pulps  in  order  to  make  them 
reaction  less. 

This  procedure  is  divided  into  three  parts  : 

Cauterization  of  the  pulp. 

Excision  of  the  crown-pulj). 

Introduction  of  a  medicament  over  which  the  final  fill- 
ing may  be  placed. 

In  order  to  obtain  satisfactory  results  from  the  very 
valuable  procedure  of  pulp-amputation,  it  is  desirable  to 


282      TREATMENT  OF  DISEASES  OF  THE  PULP. 

be  as  antiseptic  as  possible,  and  this  is  obtained  only  by 
following  a  certain  strict  technic  as  follows  : 

After  one  or  two  days  of  application  of  arsenic  (arsenic 
with  creosote  and  some  tannin),  the  cavity  is  scrupulously 
freed  of  all  carious  tooth  tissue  and  without  disturbing 
the  pulp,  is  prepared  for  the  reception  of  the  filling. 

The  cavity  is  then  bathed  in  a  strong  antiseptic.  Kext 
a  drill,  which  has  been  previously  sterilized  and  drawn 
through  creosote,  is  pushed  through  the  tissue  of  the  pulp 
cavity,  and  the  crown  pulp  cut  out. 

The  cavity  is  then  aycII  washed  with  sterilized  warm 
water,  and  a  pledget  of  cotton  saturated  with  an  anti- 
septic, such  as  a  10  per  cent,  solution  of  formaldehyd  or 
creosote,  is  then  introduced  into  the  now  clean  and  empty 
pulp  chamber.  This  pledget  of  cotton  is  then  tempo- 
rarily protected  from  the  saliva  by  means  of  collodium 
and  cotton. 

While  these  remedies  are  acting,  a  pellet  is  prepared 
by  wrapping  the  selected  medicament  in  sterilized  tin- 
foil, and  shaping  it  into  the  form  and  size  of  a  large 
wheat  kernel.  As  this  pill  has  been  handled  by  the 
fingers  it  should  be  immediately  immersed  in  a  small  dish 
containing  creosote. 

Baume  has  recommended  borax  as  an  antiseptic ;  as 
this  diffuses  so  rapidly,  w'e  mix  it  wdth  eugenol  to  form  a 
paste.  This  borax-eugenol  paste  causes  an  aseptic  col- 
liquation  necrosis  of  the  root-pulp.  The  latter  becomes 
so  liquefied  that  after  about  one  year's  time  the  canals  are 
found  completely  empty.  Another  paste,  consisting 
of  tannin  and  creosote,  leads  to  complete  destruction, 
and  is  especially  valuable  when  suppuration  of  the  pulp 
exists. 

After  the  diseased  tooth  is  made  thoroughly  dry,  the 
collodium  and  cotton  plug  as  well  as  the  antiseptic  cotton 
in  the  cavity  are  removed.  The  pill  is  passed  directly 
from  the  dish  of  creosote  into  the  pulp  chamber,  in  which 
it  is  compressed  ])y  means  of  a  sterilized  plugger. 

The  pill  is  of  the  proper  size,  and  completely  fills  the 
pulp  chamber.     If  it  be  too  small,  all  the  root  pulps  wdll 


DISEASES  OF  THE  HOOT-MEMBRANE.  283 

not  be  covered,  and  if  it  be  too  large,  it  cannot  be  properly 
applied  to  the  Malls  of  the  cavity. 

The  cavity  above  the  pill-plug  is  then  well  bathed  with 
ether,  dried  out  with  hot  air,  and  filled  with  any  suitable 
tillino;  material.  It  must  be  remembered  that  cement 
cannot  be  employed  with  borax-eugeuol,  for  the  borax 
prevents  it  from  becoming  hard.  Plate  38  demonstrates 
the  process  of  amputation. 

DISEASES  OF  THE  ROOT-MEMBRANE 
(PERIODONTITIS.) 

As  the  name  periodontitis  implies,  inflammation  of  the 
root  membrane  is  not  only  a  process  localized  in  the  peri- 
osteum, but,  as  a  rule,  includes  the  surrounding  structure 
of  the  tooth.  At  first  the  root  membrane  is  alone  involved 
[periostitis),  M'hile  later  the  substance  of  the  bone  (osteitis) 
and  the  bone-marrow  (osteomyelitis)  are  affected. 

Periodontitis  usually  follows  disease  of  the  pulp,  the 
septic  products  of  which  are  generally  the  immediate 
cause.  They  pass  through  the  apical  foramen  to  the  peri- 
osteum and  there  set  up  an  irritation.  Aside  from  the 
secondary  cases  of  periostitis,  primary  cases  occur  which 
are  caused  by  trauma.  Any  heavy  blow  or  pressure  upon 
the  teeth  or  periosteum  may  lead  to  direct  inflammation. 
To  this  class  also  belong  cases  in  which  the  teeth  were 
separated  too  rapidly  M'ith  rubber,  or  from  too  severe 
malletinp:  when  fillino^  with  oold.  A  host  of  other  con- 
ditions,  are  capable  of  irritating  these  tissues.  Of  chemical 
irritants  we  may  mention  mercury,  which,  after  prolonged 
use,  leads  to  an  unlimited  destruction  of  the  periodontium. 
Tlie  careless  application  of  arsenic,  even  though  locally, 
also  calls  forth  lesions  of  these  tissues.  Plate  44,  Fig.  1, 
shows  the  destructive  effect  of  arsenic. 

Patients  suffering  from  periodontitis  experience  pains 
altogether  dift'ereut  from  those  of  pulp  disease.  They  are 
less  likely  to  occur  in  spells,  but  are  more  constant,  and 
are  described  as  being  dull.  There  is  a  feeling  of  weight 
in  the  affected  tooth,  and  this  sensation   is  considerablv 


284  DISEASES  OF  THE  ROOT-MEMBBANE. 

PLATE   39. 

Fig.  1. — Acute  marginal  periodoutitis. 

Fig.  2. — Acute  apical  periodontitis. 

Fig.  3. — Acute  circumscribed  periodontitis. 

Fig.  4. — Acute  unilateral  periodontitis. 

Fig.  5. — Acute  unilateral  periodontitis. 

Fig.  6. — Chronic  diffuse  purulent  periodontitis. 

increased  when  the  patient  assumes  a  horizontal  position, 
so  that  sleep  if  it  be  at  all  possible,  will  be  disturbed.  The 
general  health  is  more  influenced  than  in  pulpitis ;  the 
patient  feels  ill,  and  especially  so  when  fever  sets  in,  which 
often  occurs  in  severe  cases. 

Aside  from  the  above  described  symptoms,  the  sensitive- 
ness of  the  tooth  on  pressure  is  of  diagnostic  significance. 
At  the  beginning  this  sign  is  not  very  pronounced, 
but  it  increases  more'  and  more,  and  is  accompanied  by 
elongation  and  loosening  of  the  teeth.  The  elongation  is 
due  to  the  swelling  of  the  root  membrane,  and  the  loose- 
ness is  a  sign  that  the  surrounding  tissues  of  the  tooth  are 
either  partially  replaced  by  soft  granulation  tissue,  or  that 
they  have  been  partially  destroyed  by  the  action  of  the 
pus.  Cold  water  is  well  borne,  while,  on  the  contrary, 
warm  water  may  cause  pain. 

According  to  the  course  and  location  of  the  periodonti- 
tis, Arkovy  has  made  the  following  classification: 

Acute  Periodontitis. 

1.  Acute  marginal  periodontitis. 

2.  Acute  apical  periodontitis, 

3.  Acute  circumscribed  periodontitis. 

4.  Acute  diffuse  periodontitis. 

5.  Acute  purulent  periodontitis. 

6.  Apical  abscess. 

7.  Toxic  periodontitis. 

Chronic   Periodontitis. 

1.  Chronic  apical  periodontitis. 

2.  Chronic  diffuse  periodontitis. 


7hb.39. 


Fig.  I. 


Fiq.Ji. 


Fig.3. 


Fig.  4 


Fig.  6. 


Fig.  a. 


ACUTE  PERIODONTITIS.  285 

3.  Chronic  purulent  periodontitis. 

4.  Chronic  granulomatous  periodontitis. 

5.  Apical  necrosis. 

6.  Total  necrosis. 


ACUTE  PERIODONTITIS. 

Acute  marginal  periodontitis  (acute  inflam- 
mation of  the  root  membrane)  (Plate  39,  Fig.  1)  is 
caused  by  mechanical  influences,  such  as  tartar,  and 
protruding  or  overlapping  fillings.  It  may  also  possibly 
arise  from  chemical  causes,  such  as  stagnating  remnants 
of  food  which  have  settled  at  the  neck  of  the  tooth  and 
there  undergone  fermentation.  This  chemical  origin  is 
probably  the  most  frequent.  It  occurs  mainly  between 
two  teeth,  and  leads  the  patient  to  believe  that  their  pain 
is  located  between  the  teeth.  The  interdental  papilla  is 
also  involved  in  the  process  and  is  reddened  and  painful. 

Acute  apical  periodontitis  (acute  inflammation 
of  the  tips  of  the  roots  Plate  39,  Fig.  2)  may  be  caused 
by  a  large  number  of  pulp  diseases,  and  occurs  either  at 
the  termination  of  such  diseases  or  sets  in  simultaneously 
with  total  inflammation  of  the  pulp.  Inasmuch  as  any 
vertical  pressure  is  keenly  felt,  biting  is  impossible. 

Acute  circumscribed  periodontitis  (acute  circum- 
scribed inflammation  of  the  root-membrane)  (Plate  39, 
Fig.  3)  originates  either  in  trauma  or  total  inflammation 
of  the  pulp  ;  in  such  cases  it  is  secondary.  It  may  also 
liave  an  idiopaihic  origin,  as,  for  instance,  when  the  whole 
organism  is  in  a  weakened  condition  because  of  some  fore- 
going sickness.  The  symptoms  are  not  very  decided. 
The  patient  experiences  a  discomfort  rather  than  a  pain  ; 
the  latter  occurs  only  when  pressure  is  directed  toward 
the  diseased  area,  ande  unUater(d  pet'iodoufitis,  which  is 
ilhistrated  on  Plate  39,  Figs.  4  and  5  also  belong  to  this 
class. 

Acute  diffuse  periodontitis  (acute  extensive  inflam- 
mation of  the  root-membrane)  is  usually  secondary  to  the 
apical  or  unilateral  form,  and  represents  a  complication  of 


286  DISEASES  OF  THE  ROOT-MEMBBANE. 

PLATE   40. 

Fig.  1. — Acute  puruleut  periodoutitis. 

Fig.  2. — Hypertrophic  periodontitis,  (or  chronic  diffuse). 

Fig.  3. — Apical  necrosis. 

Fig.  4. — Total  necrosis. 

Fig.  5. — Interradicular  abscess. 

Fig.  6. — Interradicular  abscess. 

a  prolonged  destructive  process  of  the  pulp.  Edema  of 
the  surrounding  soft  parts  is  often  accompanied  by  fever. 

Acute  purulent  periodontitis  (acute  suppurative 
inflammation  of  the  root-membrane)  (Plate  40,  Fig.  1)  is 
particularly  likely  to  develop  in  conjunction  with  suppura- 
tive inflammations  of  the  pulp,  but  has  also  been  observed 
to  follow  gangrene  of  the  pulp,  and  to  occur  in  dead,  senile 
roots,  through  the  canals  of  which  some  form  of  infection 
found  its  w-ay.  The  process  is  either  circumscribed  or 
diffuse.  The  disease  is  very  severe,  and  occasions  alarm- 
ing symptoms  such  as  chills  and  edema. 

Apical  abscess  (abscesses  of  the  apical  region  of  the 
roots)  represents  a  small,  soft,  red  or  yellow  swelling,  which 
is  attached  to  the  tip  of  a  root.  An  incision  shows  that 
it  is  a  very  thin  sack  filled  with  pus.  In  the  author's 
opinion,  it  is  questionable  whether  this  condition  is  not 
really  a  granuloma  of  the  root  which  has  undergone  puru- 
lent degeneration. 

This  condition  is  usually  associated  wdth  gangrene  of 
the  pulp.  Next  to  the  tips  of  the  roots  and  their  neighbor- 
hood, the  area  of  predilection  is  situated  at  the  point  of 
division  of  the  roots  in  those  teeth  having  multiple  roots, 
{interradicular  abscess)  (Plate  40,  Figs.  5  and  6). 

Toxic  periodontitis  is  chiefly  caused  by  mercurial 
poisoning  in  the  diffuse  form,  or  by  the  action  of  arsenic,  in 
Avhich  case  the  periosteum  is  inflamed  and  mortified  to 
a  more  or  less  large  extent.  This  may  lead,  in  fact,  as  is 
shown  on  Plate  44,  Fig.  1,  to  partial  necrosis  of  tlie  bone. 
For  this  reason  arsenic  applications  must  be  well  protected. 


Tab.^0. 


Iig.l. 


Eig.2. 


Fig.3. 


Fig.  4 


Fig. 


fig.  ti. 


CHRONIC  PERIODONTITIS.  287 

CHRONIC    PERIODONTITIS. 

Chronic  apical  periodontitis  (chronic  inflammation 
of  the  tips  of  the  roots)  is  caused  by  chronic  diseases  of  the 
pulp.  It  is  manifested  by  a  thickening  of  the  periosteum 
in  the  fundus  of  the  alveolus.  If  this  condition  becomes 
more  extensive,  we  speak  of  chronic  diffuse  periodontitis. 

Chronic  diflPuse  periodontitis  (chronic  diffuse 
inflammation  of  the  root-membrane).  In  this  disease  the 
root-membrane  is  considerably  hypertrophied,  and  may 
lead  to  such  a  pronounced  form  as  that  illustrated  on 
Plate  40,  Fig.  2. 

Chronic  purulent  periodontitis  (chronic  suppura- 
tive inflammation  of  the  root-membrane)  is  a  diseased  con- 
dition into  which  the  root-membrane  passes  after  a  long 
standing  acute  suppurative  inflammation.  Such  teeth 
suffer  but  little  pain,  the  gums  lie  loosely  about  them,  and, 
when  the  tooth  is  pressed,  a  considerable  amount  of  pus  is 
forced  out.     (Plate  39,  Fig.  6.) 

Chronic  Granulomatous  Periodontitis. — A  gran- 
uloma of  the  root,  which  term,  strictly  speaking,  should 
include  all  hyperplasise  of  the  root-membrane,  consists, 
as  the  name  implies,  chiefly  of  granulation  tissue.  Since 
the  latter  is  supplied  more  or  less  abundantly  with  epithe- 
lium, its  consistency  varies  considerably.  As  these  little 
growths  have  the  tendency  after  a  long  period  of  time  to 
form  root-cysts,  which  require  surgical  interference,  it  has 
been  discussed  elsewhere  under  cvsts.  (Page  122). 

Necrosis  of  the  apex  and  total  necrosis  (Plate 
40,  Figs.  3  and  4)  do  not  really  belong  to  the  diseases  of 
the  root-membrane  for  they  are  a  sequel  to  them.  The 
process  concerned  consists  in  the  death  of  the  cement  cells, 
either  on  account  of  long  standing  suppurative  inflamma- 
tion of  the  root-membrane,  or  as  a  result  of  senile  changes. 
The  disease  is  recognized  in  extracted  teeth  by  the  fact 
that  the  roots  show  a  light-gray  to  a  black  discoloration. 
In  the  early  stage  the  surface  is  still  smooth,  later,  however, 
it  becomes  rough,  ])artly  because  of  typical  resorptive 
processes,  and  partly  because  of  erosions  due  to  the  pus. 


288  DISEASES  OF  THE  HOOT-MEMBBANR    ' 

PLATE  41. 

Fig.  1.— Fistula. 

Fig.  2. — Alveolar  pyorrhea.  The  gum  is  loose,  and  in  the  resulting 
pockets  yellowish  pus  may  be  seen.  Dark  crusts  are  attached  to  the 
roots  and  the  surrounding  bone  is  undergoing  destruction. 

Teeth  showing  symptoms  of  necrosis  of  the  roots  are 
difficult  to  cure,  for  the  organism  acts  upon  the  dead  cement 
substance,  as  upon  foreign  bodies,  and  attempts  to  dis- 
charge it. 

THE  COURSE  OF  INFLAMMATIONS  OF  THE 
ROOT-MEMBRANE. 

Since  inflammations  of  the  root-membrane  are  usually 
due  to  some  septic  irritant,  they  exist  so  long  as  this 
irritant  is  present,  and  spontaneous  healing  is  therefore 
impossible.  The  subjective  symptoms  mayindeed  become 
less  severe,  yet  this  usually  indicates  that  the  acute  has 
passed  into  the  chronic  stage. 

As  a  rule,  the  bone  becomes  swollen  in  the  neighbor- 
hood of  the  diseased  area  ;  this  indicates  that  the  bone 
marrow  and  the  bone  are  sharing  the  inflammation.  Aside 
from  these  strictly  local  symptoms,  the  nearby  soft  parts, 
like  the  lips  and  cheeks,  also  become  swollen.  Indeed, 
in  some  rare  cases  the  inflammation  may  become  so  exten- 
sive, and  so  much  edema  develop,  that  the  patient's  life  is 
in  danger.  The  regional  lymph  glands  of  the  lower  jaw 
and  the  neck  are  also  involved. 

The  chief  event,  however,  is  the  formation  of  pus 
which  seeks  an  exit  in  every  direction.  Since  there  exists 
in  the  region  of  the  neck  of  the  tooth  no  marginal  opening 
(Plate  43,  Fig.  2  a),  the  pus  passes  through  the  bone,  and 
appears  first  underneath  the  periosteum,  which  is  thus 
caused  to  bulge  out.  This  swelling,  because  of  its  limited 
rounded  form  and  hard  consistency,  is  not  rarely  mistaken 
for  a  bony  growth.  (See  Plate  42,  Fig.  1,  subperiosteal  ab- 
scess.) The  pus  breaks  through  the  periosteum  after  a  time 
and  reaches  underneath  the  gum  (periosteal  abscess,  Plate 
43,  Fig.  1),  from  where  it  travels  rapidly  through  the  sur- 
rounding soft  tissues.     As  a  result,  the  general  swelling 


Tah.^1. 


lig.l. 


Fig.Ji. 


COURSE  OF  INFLAMMATION  OF  ROOT-MEMBRANE.  289 

increases,  but,  as  now  the  tension  of  the  bone,  and  of  the 
periosteum  has  been  lessened,  the  pains  disappear. 

All  swellings  of  the  ja^y  caused  by  pus,  whether  they 
are  situated  deeply  in  the  bone  or  on  the  surface,  are 
designated  as  2^<^^^'ulis.  Since  the  pus  usually  penetrates 
toward  the  labial  side,  the  parulis  is  most  often  found 
on  the  side  toward  the  lips  or  cheeks.  When  the  parulis 
is  sufficiently  filled,  it  ruptures  spontaneously,  and  the  pus 
is  discharged  into  the  mouth.  Later  the  parulis  fills  itself 
repeatedly,  but  empties  itself  continually,  for  the  mucous 
membrane  after  it  has  once  been  weakened  easily  ruptures, 
and  allows  the  escape  of  the  pus  before  it  expands  to  a 
large  size.  Finally,  it  no  longer  becomes  swollen,  but  the 
pus  formed  in  the  neighborhood  of  the  tooth  continually 
discharges  itself  outwardly  ;  that  is,  a  fistula  of  the  gum 
has  been  created.  Not  only  is  the  gum  ruptured,  but  the 
spongiosa,  aud  even  the  compacta,  may  become  partially 
necrotic  and  destroyed.  Plate  44,  Fig.  2,  shows  a  begin- 
ning necrosis.  In  chronic  cases  so-called  blind  abscesses 
may  be  formed,  such  as  illustrated  on  Plate  42,  Fig,  2. 
These  usually  remain  small  and  cause  the  patient  little  or 
no  pain. 

The  pus  penetrates  the  upper  jaw  toward  the  hard 
palate  less  frequently,  because  in  that  direction  the  bone 
possesses  considerable  thickness.  It  collects  at  first 
underneath  the  periosteum  and  causes  it  to  pufp  out,  under 
which  circumstances  the  swelling  feels  hard.  Next  the 
pus  readies  lielow  the  gum  where  the  palpating  finger  can 
])lainly  detect  fluctuation.  This  swelling  interferes  de- 
cidedly with  speaking  and  masticating.  Fig.  56  6,  upper 
illustration,  presents  the  rare  case  of  double-sided,  sub- 
. periosteal  abscess.  In  the  upper  jaw  the  pus  may  travel 
in  other  directions,  for  example,  toward  the  nasal  cavity 
and  toward  the  antrum  of  Hio-hmore.  In  the  last  case 
an  empyema  maybe  simulated,  or  when  the  pus  stagnates 
an  empyema  may  be  induced. 

One  of  the  rarest  of  occurrences  is  an  abscess  formation 
on  the  lingual  side  in  the  region  of  the  lower  molars.  The 
pus  does  not  collect  here,  because  the  plate  of  bone 
19 


290  DISEASES  OF  THE  ROOT-MEMBBANE. 

PLATE  42. 

Fig.  1. — Subperiosteal  abscess. 

a.  Collection  of  pus. 
6.  Periosteum. 
c.  Mucous  membrane. 
Fig.  2. — Blind  abscess. 

PLATE  43. 

Fig.  1. — Periosteal  abscess. 

a.  Collection  of  pus. 
6.  Periosteum. 
c.  Mucous  membrane. 
Fig.  2. — Periosteal  abscess. 

a.  Marginal  opening  of  the  same. 

is  quite  thin  near  the  points  of  the  roots.  This  plate, 
therefore,  does  not  bulge  out,  but  is  rapidly  ruptured 
to  permit  the  pus  to  flow  into  the  submaxillary  tissues 
which  become  swollen. 

The  laity  fears  the  most  the  exit  of  the  pus  through 
the  outer  skin,  because  it  always  results  in  the  formation 
of  a  scar.  In  fact,  a  fistula  may  be  established  through 
the  cheek,  but  as  a  rule  the  pus  penetrates  the  outer  skin 
at.  the  lower  jaw  and  occasionally  at  the  neck. 

The  attempt  is  usually  made  to  seek  the  diseased  tooth 
in  the  neighborhood  of  the  swelling  or  of  the  fistula. 
This  is,  as  a  rule,  a  proper  procedure,  but  one  must  not 
disregard  the  fact  that  a  buri'owing  abscess  may  exist 
which  runs  a  hidden  course.  For  instance,  it  may  be 
observed  that  an  abscess  appears  in  the  region  of  the 
incisor  teeth  of  the  lower  jaw,  whose  origin  is  in  the 
second  molar,  or  a  fistula  may  appear  in  the  palatal  tissue 
in  the  region  of  the  molar  teeth,  with  the  source  in 
a  central  incisor. 

TREATMENT  OF  INFLAMMATION  OF  THE  ROOT- 
MEMBRANE. 

If  the  periodontitis  is  found  in  its  beginning  stages, 
the  formation  of  pus  should  be  actively  counteracted,  and 
for  that  purpose  it  is  necessary  to  determine  the  causal 
factor.  As  this  is  usually  due  to  partially  or  completely 
destroyed  remnants  of  the  pulp,  they  must  be  carefully 


Iig.l. 


Fi(f.^. 


Fig.l. 


Ficf.^. 


INFLAMMATION  OF  ROOT-MEMBRANE 


291 


removed  and  the  root  canal  sterilized,  exactly  as  in  the 
case  of  gangrene  of  the  pulp,  as  described  on  page  280. 
1^  pus  has  already  formed,  the  most  satisfactory  results 
are  obtained  in  treating  the  root  ;  that  is,  opening 
the  latter  so  that  the  pus  may  be  discharged  through  the 
root  canal.     This  means  the  formation  of  a  blind  abscess. 


Fig.  136.— a  macerated  upper  jaw  in  which  an  oval  section  of  the  facial 
alveolar  wall  was  destroyed  by  the  formation  of  pus  following  a  periostitis  of 
the  first  bicuspid  tooth. 

as  is  demonstrated  on  Plate  42,  Fig.  2.  In  such  cases,  it 
is  not  advisable  to  introduce  antiseptic  fillings  into 
the  root  at  once,  it  being  -wiser  to  allow  the  tooth 
to  remain  open  for  several  days.  The  further  treatment 
is  like  that  of  a  gangrenous  pulp.  A  parulis  should 
be   incised,  but   the  kuife  must  be  forced  deeply  into 


292  DISEASES  OF  THE  ROOT-MEMBRANE. 

PLATE  44. 

Fig.  1. — Toxic  periodontitis  (due  to  arsenic).  A  protruding  deposit 
of  arsenic  caused  destruction  at  (a),  not  only  of  the  gum,  but  to  a  certain 
extent  of  the  periosteum  and  the  bone. 

Fig.  2. — Beginning  necrosis  of  the  bone.  The  continuous  formation 
of  pus  has  caused  necrosis  of  the  substance  of  the  bone  at  (a). 

the  mucous  membrane,  which  is  often  very  thick,  in  order 
that  the  occasionally  excessive  amount  of  pus  can  be 
discharged.  The  introduction  of  a  tamjjon  of  iodoform 
gauze  will  prevent  the  premature  closure  of  the  wound 
edges. 

Of  external  remedies,  loarmth  is  much  employed. 
Occasionally  the  inflammation  may  be  lessened  by  painting 
the  part  with  iodin  and  aconite  (simultaneously  applied). 
Formerly,  leeches  were  given  the  preference,  and,  indeed, 
with  good  results.  Since  the  effects  are  most  satisfactory, 
and  as  infection  of  the  oral  cavity  by  the  leech  is  unheard 
of,  this  procedure  is  to  be  recommended  in  certain  cases. 

If  the  inflammation  respond  to  none  of  these  remedies, 
excision  of  the  diseased  tip  of  the  root,  as  has  been 
recommended  in  recent  times  by  Weiser,  is  indicated,  and 
eventually  replantation  may  be  done. 

Replantation  or  reimplantation  is  an  operation  in  which 
an  extracted  tooth,  after  the  removal  of  the  diseased 
portion  of  the  root,  is  returned  to  its  socket,  in  order  that 
it  may  again  heal  into  place.  In  transplantation,  the 
extracted  tooth  is  inserted  in  a  foreign  alveolus,  that  is, 
in  one  it  had  not  occupied  previously. 

In  performing  this  operation,  it  is  necessary  that 
the  tooth,  which  is  to  be  inserted,  be  in  as  fresh  a  condition 
as  possible,  because  its  union  with  the  alveolar  wall 
occurs  much  sooner,  when  the  periosteal  cells  on  the  roots, 
as  well  as  the  cement  cells,  are  still  living.  For  this 
reason,  none  of  the  tissues  should  be  subjected  to  injurious 
disinfectants,  but,  instead,  the  tooth,  as  well  as  the 
alveolus,  are  only  treated  with  a  physiological  salt 
solution ;  by  following  this  advice  many  failures  may  be 
avoided. 

If  the  roots  fit  the  alveoli,  nothing  needs  to  be  done 
excepting  to  fill  the  root  canal  and  all  existing  defects, 


TahA^. 


Fuf.2. 


EXTRACTION  OF  TEETH.  293 

inserting  the  tooth  into  place  and  applying  a  fixation 
band  (ligature,  splint,  etc.).  In  favorable  cases  the  tooth 
iicals  tightly  into  place,  so  that  it  may  again  become  useful. 
If,  however,  no  alveolus  exists,  or  it  does  not  permit  the 
entrance  of  the  root,  it  is  necessary  to  drill  an  opening 
in  the  alveolar  process  by  means  of  suitable  bone-burs,  etc. 

Such  implanted  teeth  sometimes  grow  tightly  in  place 
l)v  means  of  a  connective-tissue  union  (pseudoarthrosis) 
and  functionate  for  many  years.  However,  these  teeth 
are  constantly  attacked  by  absorption  processes,  which, 
after  a  shorter  or  lonp-er  time  lead  to  their  loss. 

It  has  been  attempted  to  prevent  these  resorption  pro- 
cesses by  forming  roots  from  porcelain  or  metal,  but  no 
good  results  have  thus  far  been  achieved. 

We  find  ourselves,  therefore,  in  a  difficult  dilemma  as 
concerns  replantation,  from  which  we  cannot  hope  to  soon 
escape.  If  we  select  a  natural  root-material,  the  root 
becomes  absorbed  (and  with  it  some  of  the  alveolus  or 
surrounding  tissue),  and  if  we  select  an  artificial  insoluble 
voot-material,  the  structures  surrounding  the  root  are 
absorbed.  As  various  as  are  the  methods  of  this  oper- 
ation, equally  so  are  the  results,  and  after  a  shorter  or 
longer  time  the  teeth  become  loose  and  are  lost.  In  spite 
of  many  failures,  success  occasionally  is  met  with,  and, 
therefore,  we  are  always  inclined  to  resort  to  replantation 
time  and  again.  If  none  of  the  mentioned  forms  of  treat- 
ment succeed,  necrotic  roots  when  found  should  be 
exti'cided. 

EXTRACTION  OF  TEETH, 

INDICATIONS. 

Since  the  enormous  value  of  the  teeth  to  the  economy 
has  been  discovered,  it  is  one's  duty  to  determine  before 
each  extraction  wdiether  such  a  procedure  is  justified. 
For  that  reason  we  will  consider  the  individual  causes 
which  would  absolutely  warrant  the  removal  of  a  tooth. 

I/Oose  teeth,  which  in  sjnte  of  all  therapy  cannot  be 
fastened,  often  cause  discomfort  and  pain,  on  account  of 


294  EXTRACTION  OF  TEETH. 

which  their  removal  is  necessary.  The  loosening  is 
usually  clue  to  disappearance  of  the  alveolar  borders  in 
consequence  of  senile  atrophy,  atrophia  prsecox,  alveolar 
pyorrhea,  or  chronic  suppurative  inflammation  of  the 
root-membrane. 

Carious  teeth  are  rarely  extracted  in  modern  times 
by  scientific  dentists.  Even  when  the  crown  has  been 
destroyed  to  a  considerable  depth,  the  tooth  may  still,  by 
suitable  treatment,  be  made  functionating  or  at  least 
reactionless.  Only  in  those  cases  in  which  this  can  no 
longer  be  achieved,  or  when  from  disease  the  tooth  pre- 
vents the  insertion  of  a  substitute  tooth,  is  extraction 
justified. 

It  occurs  also  that  a  sound  tooth  must  be  sacrificed  in 
applying  artificial  teeth,  when,  for  example,  only  a  single 
elongated  cuspid  tooth  remaining  in  the  jaw  prevents  an 
aesthetic  treatment  of  the  mouth.  Occasionally  super- 
numerary or  regular  teeth  have  grown  so  far  out  of  the 
tooth-row  that  correction  is  better  attained  by  extraction 
than  by  pressing  them  back  into  position. 

Sometimes  a  patient  calls  after  a  night  of  much  pain, 
and  begs  one  to  extract  a  tooth,  which  has  been  attacked 
by  an  acute  inflammation  of  the  root-membrane.  If  the 
patient  is  weak  and  nervous,  and  cannot  bear  a  prolonged 
treatment,  or  if  this  process  has  repeatedly  returned,  we 
need  not  hesitate  to  comply  with  his  request. 

Diseases  of  the  jaw-bone,  like  osteitis,  necrosis,  gangrene 
(noma),  abscess  or  fistula  formation,  demand  extraction 
of  the  suspected  teeth.  In  nearly  all  these  cases  it  is 
usually  possible  to  diagnosticate  necrosis  of  the  cement 
or  roots.  This  necrosis  is  either  the  result  or  more  fre- 
quently the  cause  of  disease  of  the  bone.  Dead  teeth 
which  have  become  necrotic  should  be  extracted  as  soon 
as  they  cause  any  symptoms,  for  they  irritate  the  surround- 
ing tissue  and  their  roots  become  absorbed. 

If  teeth  cause  serious  neuralgia  they  must  be  extracted 
in  certain  cases  ;  in  the  diiferent  forms  of  pulpitis  con- 
servative treatment  should  be  first  instituted.  This  treat- 
ment, however,  does  not  suffice  in  the  case  of  thickening 


INDICATIONS. 


295 


Fig.    137.— Position  in  extracting  a  touth  from  the  left  upper  jaw. 


296  EXTRACTION  OF  TEETH, 

of  the  root-cement  (exostoses),  and  occasionally  when 
there  is  an  odontoma  of  the  inner  walls,  a  condition  which 
was  described  by  J.  Scheff. 

Extraction  of  the  upper  first  or  second  molar,  becomes 
necessary  in  empyema,  when  one  of  these  teeth  has  caused 
the  empyema,  or  when  in  the  course  of  treatment  it  is 
desired  to  drain  the  antrum  of  Highmore,  through  the 
alveolar  process. 

CONTRAINDICATIONS. 

In  hemophilia  we  must  not  fail  to  realize  that  a  fatal 
hemorrhage  may  follow  an  extraction.  If  in  spite  of  this 
disease  the  operation  must  be  performed,  we  must  not  feel 
content  if  the  blood  ceases  to  flow  soon  after  the  extrac- 
tion, for  frequently  a  fatal  outflow  of  blood  develops  some 
time  later,  as  in  the  night  for  instance.  Severe  hemor- 
rhages are  especially  to  be  dreaded  in  nephritis,  scorbutus, 
purpura  hemorrhagica,  and  leukemia. 

In  certain  cases  oi pregnancy,  when  the  woman  is  weak 
and  exhausted,  or  Avhen  it  is  known  that  considerable 
pain  will  be  caused  by  the  operation,  extraction  is  contra- 
indicated.  If,  however,  palliative  treatment  gives  no 
relief  it  is  wiser  to  inflict  a  short  pain  upon  the  patient 
than  to  let  her  suffer  for  a  long  time.  The  same  regula- 
tions hold  true  for  women  during  lactation  and  menstrua- 
tion. 

Opinion  varies  as  to  the  propriety  of  extraction  in  the 
presence  of  edema  or  maxillary  abscess.  Some  claim  there 
is  danger  of  pyemia  and  septicemia,  whereas  others  have 
not  observed  such  results.  The  author,  however,  is  ac- 
quainted with  two  cases  in  which  extraction  was  followed 
by  phlegmonous  degeneration  and  death.  In  one  case  the 
cheek  was  swollen  before  the  operation,  but  not  so  in  the 
other.  It  is  not  advisable  to  extract  a  tooth  when  it  is 
associated  with  inflammatory  edema  in  a  weak  patient, 
who  is  worn  out  from  disease,  for  in  that  case  serious  con- 
sequences may  easily  result. 


CONTBAINDICA  TIOXS. 


297 


I 


^ 


7 


Fig.  138.— Position  in  extracting  a  tooth  from  the  right  upper  jaw. 


298 


EXTRACTION  OF  TEETH. 


THE  TECHNIC  OF  EXTRACTION. 
Before  beginning  an  extraction  the  instrument  must  be 
absolutely  clean  and  if  possible,  sterile,  for  there  is  dan- 
ger of  transmitting  disease  through  them.    The  teeth  and 
the  gums  of  the  side  concerned  should  likewise  be  thor- 


FiG.  ]39.-Positiou  in  extraction  of  a  tooth  from  the  left  lower  jaw. 

oughly  cleaned,  in  order  that  the  attached  deposits  be  not 
inoculated.  The  writer  insists,  both  in  private  practice 
and  in  the  clinics,  that  each  tooth  be  washed  with  ether 


EXTRACTION  OF  THE  UPPER   TEETH.         299 

before  the  extraction.  Rubbing  them  with  ether  does  not 
only  free  the  teeth  and  gums  of  unclean  material,  but 
also  causes  a  slight  amount  of  anesthesia. 

It  is  perhaps  of  value  to  the  beginner  to  become  ac- 
quainted with  the  following  fundamental  principles  which 
bear  upon  the  manipulation  of  the  forceps  : 

The  forceps  must  be  passed  up  along  the  neck  of  the 
tooth  as  far  as  possible.  They  must  not  be  pressed  to- 
gether more  tightly  than  is  necessary  for  a  firm  hold, 
otherwise  there  is  a  risk,  especially  in  deep  caries  and 
brittle  teeth,  of  breaking  the  tooth  off  even  in  simply 
applying  the  instrument. 

Attempt  at  first  through  slow  "  working  "  to  loosen  the 
tooth,  and  gradually  apply  more  and  more  force  to  the 
movements.  Instead  of  loosening  the  tooth  from  its  attach- 
ment, if  it  is  forcibly  luxated  from  the  very  beginning, 
the  crown  or  a  portion  of  the  alveolar  process  may  be 
broken  oif.  Inasmuch  as  the  external  bony  plate  of  the 
alveoli  is  thinner  than  the  internal,  and  the  spongiosa  so 
formed  that  the  roots  can  arrow  longer  in  a  lingual  direc- 
tion,  more  strength  should  be  employed  in  'Svorking"  out- 
wardly than  inwardly. 

Aside  from  the  movement  for  loosenino-  it  must  not  be 
forgotten  to  give  one  tug  forcibly  downward  or  upward. 
Care  must  be  exercised  not  to  strike  and  thus  injure  the 
neighboring  teeth  with  the  forceps. 

EXTRACTION  OF  THE  UPPER  TEETH. 

In  extraction  of  the  upper  teeth,  the  patient  must  sit 
on  an  elevated  seat  with  the  head  inclined  backward. 
The  dentist  fixes  the  patient's  head  with  his  left  hand, 
and  employs  that  hand  at  the  same  time  to  draw  the  lips 
away,  in  order  to  obtain  a  good  view  of  the  mouth. 

The  position  of  the  operator  in  extracting  upper  teeth 
is  always  to  the  right  of  the  ])atient.  If  the  left  upper 
jaw  is  to  be  operated  upon  the  oj)erator  must  bend  some- 
what forward,  but  in  case  of  the  right  ui)per  jaw  he  should 
stand  at  the  right  shoulder  of  the  patient  (see  Figs.  137  and 
138). 


300 


EXTRACTION  OF  TEETH, 


Fig.  140.— Position  for  extracting  a  tooth  from  the  right  lower  jaw. 


EXTRACTION  OF  UPPER  INCISOR  TEETH.      301 


EXTRACTION  OF  THE  LOWER  TEETH. 

When  the  lower  teeth  are  to  be  extracted  the  patient 
should  be  seated  upon  a  low  seat,  and  the  head  should  be 
so  fixed  that  it  is  bent  slightly  forward. 

The  operator  should  stand  back  of  the  right  shoulder 
when  removing  teeth  from  the  right  half  of  the  lower  jaw. 
With  his  left  hand  passed  around  the  left  side  of  the 
patient's  head,  he  grasps  the  lower  jaw  in  such  a  manner 
that  the  thumb  rests  upon  the  teeth  and  the  fingers 
around  the  jaw  (see  Fig.  140). 


Fig.  141.— Forceps  for  upper  incisor  and  cuspid  teeth. 

In  extraction  of  teeth  from  the  left  lower  jaw  the  oper- 
ator stands  likewise  at  the  right  side  and  a  little  in  front 
of  the  patient.  But  as  this  position  interferes  somewhat 
with  the  light,  it  is  better  to  stand  wholly  on  the  left  side. 
Xaturally  in  this  position  it  is  imjDOSsible  to  clasp  the 
hand  around  the  head  of  the  patient,  and  therefore  the 
opposite  side  of  the  jaw  should  be  simply  grasped  with 
the  left  hand  (see  Fig.  139). 

THE    EXTRACTION  OF  UPPER  INCISOR    AND  CUSPID 
TEETH. 

The  same  ]>air  of  forceps  is  usually  employed  for  ex- 
traction of  the  upjier  incisor  and  cuspid  teeth.  Its  jaws 
are  a  direct  continuation  of  the  handles  (Fig.  141).  One 
may,  however,  select  one  of  a  large  number  of  models,  so 
long  as  the  jaws  are  formed  to  exactly  fit  the  oval  shape 
of  the  roots.     The  groove  of  the  labial  jaw  should  really 


302 


EXTRACTION  OF  TEETH. 


be  wider  than  that  of  the  lingual,  because  the  roots  are 
thicker  in  front  than  behind. 

With  such  a  pair  of  forceps,  the  tooth  is  grasped 
as  high  up  on  the  neck  as  possible,  and  rotated  on  its 
long  axis.  This  manipulation  is  usually  sufficient  to 
loosen  the  central  incisors,  for  their  roots  are  rounded. 
But  if  unexpected  curvatures  or  abnormalities  in  the 
thickness   and    length,    etc.,    of  the    roots    exist,   which 


Fig    142. — Forceps  for  lower  incisors,  cuspids  and  bicuspids. 

are  easily  detected  by  the  enlargement  of  the  parts, 
it  becomes  necessary  to  precede  the  rotation  by  "  loorhingJ^ 
This  is  best  performed  by  forcing  the  tooth  rapidly 
in  a  labiolingual  direction  to  and  fro,  and,  at  the  same 
time,  exerting  considerable  traction  in  a  labial  and 
downward  direction. 

This  manipulation  is  similar  for  the  lateral  incisor 
teeth,  but,  as  their  roots  are  more  tightly  pressed  together 
in  a  lateral  direction,  not  much  assistance  is  obtained 
through  rotation.  Better  results,  in  that  case,  follow 
working,  which,  however,  must  be  carefully  performed  in 
order  to  prevent  a  fracture  of  the  roots. 


Fig.  U3.— Forceps  for  upper  bicuspids  and  for  certain  roots  of  the  upper  jaw. 

The  upper  cuspid  teeth  are  known  to  have  the  largest 
and  strongest  roots,  which  are  set  in  much  stronger 
alveoli  than  the  incisor  teeth.  They  must,  therefore,  be 
grasped  at  as  high  a   point  as  possible,  and  it  is  often 


EXTRACTION  OF  THE   UPPER  MOLAR  TEETH.   303 

necessary  to  exert  considerable  strength  in  order  to  loosen 
them,  through  rotation  and  luxation. 

THE  EXTRACTION  OF  LOWER   INCISOR  AND   CUSPID 
TEETH. 

For  the  extraction  of  these  teeth,  a  pair  of  forceps 
is  necessary,  whose  jaws  stands  at  right  angles  to  the 
handles  (see  Fig.  142).  The  lower  incisors  have  small, 
laterally  compressed  roots,  on  account  of  which  it  is 
impossible  to  remove  them  by  a  twisting  motion,  but, 
instead,  they  should  be  forced  toward  the  lips ;  this 
one  movement  of  luxation  is  sometimes  sufficient  to 
remove  the  tooth. 

The  loioer  cuspid  teeth  are  fastened  by  means  of  long, 
laterally  compressed  roots,  on  account  of  which  it  is 
necessary  to  employ  considerable  strength ;  usually, 
it  is  necessary  to  resort  to  the  "  working "  movement 
repeatedly,  in  order  to  remove  the  tooth. 

THE   EXTRACTION   OF   THE   UPPER   BICUSPIDS    AND 
MOLARS. 

The  roots  of  the  first  upper  bicuspids  are  pressed 
tightly  against  each  other,  and  are  often  divided  into 
two  parts. 

The  second  upper  bicuspids,  as  a  rule,  possess  only 
one  root.  For  the  extraction  of  this  tooth,  it  is  best 
to  employ  the  bayonet-shaped  forceps  shown  in  Fig.  143. 
Since  these  roots  are  often  very  tender  and  brittle, 
they  must  be  grasped  at  a  high  position,  and  loosened 
from  their  surroundings  by  slow  and  careful  luxation. 

As  we  know,  the  upper  molars  ])ossess  three  roots,  two 
of  which  are  located  on  the  buccal  side,  and  one  on 
tlie  palatine  side.  On  account  of  this  arrangement, 
the  jaws  of  the  forceps  must  have  two  notches  on 
the  buccal  side,  and  one  on  the  palatinal.  In  order 
that  tlie  molars  may  be  conveniently  gras])ed,  the  jaws 
of  the   forceps   should  form  an  obtuse  angle  with   the 


304  EXTRACTION  OF  TEETB. 

handles.     It  is,  therefore,  necessary  to  have  a  separate 
pair  of  forceps  for  each  side.     (See  Figs.  144  and  145.) 

Naturally,  the  upper  molars  cling,  as  a  rule,  very 
tightly  to  their  alveoli,  but,  by  means  of  a  careful  to 
and  fro  movement,  it  is  usually  possible  to  withdraw 
all  three  of  the  roots  simultaneously.  During  this 
procedure,  the  pressure  should  be  mostly  exerted  in 
the  buccal  direction,  because  of  the  thinness  of  the  outer 


Fig.  144. — Forceps  for  left  upper  molar  teeth. 


Fig.  145.— Forceps  for  right  upper  molar  teeth. 

plate  of  bone.  If  the  crown  is  already  so  deeply  destroyed 
that  it  is  no  longer  properly  connected  with  the  roots, 
it  is  wiser  to  remove  them  one  by  one  with  the  bayonet 
forceps.  The  same  forceps  are  employed  for  the  third 
molar  or  so-called  vnsdom  teeth,  especially  when  they 
are  abnormally  small. 


EXTRACTION  OF  THE  LOWER  MOLARS.        305 

THE  EXTRACTION  OF  THE  LOWER  BICUSPIDS  AND 
MOLARS- 

Each  of  the  lower  bicuspids,  the  first  as  well  as  the 
second,  possesses  one  root,  which  appears  round  or 
oval  on  cross  section.  Similar  forceps  are  employed 
in  their  extraction  as  for  the  lower  incisor  teeth  (Fig.  142), 
and  they  are  extracted  in  exactly  the  same  manner. 
Thev  adhere  somewhat  more  tightly  to  the  jaw,  but, 
even  so,  they  too,  sometimes  drop  out  of  the  alveolus 
after  the  first  outward  movement. 

The  lower  molars  have  two  roots,  a  strong  mesial 
and  a  weaker  distal  root,  which  is  twisted  backward. 
There  is  but  one  form  of  forceps  which  acts  satisfactorily 
in  extracting  these  teeth,  the  crow-billed  forceps  pictured 
in  Fig.  146.  It  is  constructed  after  the  same  principle 
as  is  the  pair  of  forceps  used  for  lower  incisor  teeth;  that 
is,  the  jaws  form  a  right  angle  with  the  handles,  but  pos- 
sess  on  both  sides  two  notches,  into  which  the  roots  fit. 


Fig.  146.— Forceps  for  lower  molars. 

The  forceps  must  be  very  strong,  since  the  lower  molars 
set  exceptionally  tight  in  their  sockets.  The  roots  of  the 
first  lower  molars  diverge  considerably,  on  account  of  which 
they  are  held  strongly  in  place.  It  is  necessary,  therefore, 
in  order  to  remove  them  simultaneously  with  the  crown, 
to  combine  strength  with  precaution  ;  that  is,  they  must 
be  d('('|)ly  grasped,  slowly  but  energetically  luxated,  and 
linally  turned  outward.  The  roots  of  the  ^(/-o /o;/-*?/- »ioA;/'.s 
diverge  much  less  or  not  at  all,  but  they  are  inserted  in 
the  j)ortion  of  the  inferior  maxilla  which  is  thickened  on 
the  outer  side  by  the  oblique  line,  and  on  the  inner  side 
by  the  mylohyoid  line,  which  enhances  the  difficultv  of 
their  extraction.  The  same  forceps  are  employed  for  the 
20 


306 


EXTRACTION  OF  TEETH. 


wisdom  teeth  as  for  the  remaining  lower  molars.  When 
their  roots  are  poorly  developed,  the  wisdom  teeth  are  easily 
removed ;  sometimes,  however,  they  are  hooked  into  the 
jaw  with  crooked  roots.  Such  a  third  molar,  which  pos- 
sesses five  hook-like  curved  roots,  is  shown  in  Fig.  78  ; 
even  in  this  case  the  crow-billed  forceps  sufficed  for  the 
removal. 


Fig.  147.— Forceps  for  lower  molars. 


Fig.  148.— The  universal  forceps  of  Rauhe. 

Fig.  147  shows  another  form  of  forceps  for  lower  molars, 
which  is  also  recommended  by  various  practitioners. 

Universal  forceps  may  only  be  looked  upon  as  instru- 
ments which  give  assistance  in  certain  cases,  for  they  can- 
not be  properly  applied  to  teeth  in  all  localities.  The 
best  are  those  of  Rauhe,  which  are  shown  in  Fig.  148. 


EXTRACTION  OF  ROOTS. 

Roots  are,  as  a  rule,  more  difficult  to  extract  than 
teeth,  and,  when  they  remain  behind  after  an  unsuccess- 
ful tooth  extraction  their  removal  may  at  that  time  be 
impossible.  If,  therefore,  a  root  is  broken  off  in  such  a 
manner  that  it  lies  deeply  imbedded  in  the  jaw-bone,  it 


EXTRACTION  OF  ROOTS.  307 

is  wiser  to  postpone  action  and  see  whether  any  ill  effects 
develop.  There  are  many  dentists  who  believe  that  every 
fractured  root  must  be  immediately  removed.  But  as 
this  is  accompanied  by  considerable  pain,  it  can  but  imbue 
the  patient  with  great  fear  for  all  future  extractions.  It 
is,  therefore,  better  to  wait  until  the  root  has  risen 
slightly  above  the  alveolus,  which  will  surely  occur  in 
time.  It  may  then  be  removed  without  injury  to  the  sur- 
rounding tissue. 

Roots  remaining  after  the  crown  has  been  worn  off  are 
more  easily  extracted  than  those  of  fractured  teeth. 
This  is  due  to  the  fact  that  the  circular  ligament,  which 
has  usually  been  destroyed  in  these  cases,  no  longer  resists 
the  action  of  the  forceps,  and  also  because  the  walls  of  the 
alveoli  are  usually  atrophied.  Complications  which  are 
specially  difficult  arise  when  the  gum  grows  as  a  tense 
covering  over  the  root,  or  when  the  latter  is  broken  off  at 
a  point  high  up  in  the  alveolus.  In  the  first  case,  the  gum 
bridge  is  removed  by  means  of  a  knife  or  a  pair  of 
scissors  ;  in  the  last  case,  a  pair  of  forceps  with  a  cutting 
jaw  (resection  forceps)  are  required.  The  bayonet-shaped 
forceps  shown  in  Fig.  143  are  useful  in  the  extraction  of 
all  roots  of  the  upper  jaw.  The  forceps  constructed  by 
J.  Schcff,  which  have  long,  slender  jaws,  are  highly  praised 
by  some  practitioners,  because  they  can  be  passed  high 
up  between  the  gums  and  the  bone. 

If  a  root  is  broken  off  so  high  up  that  it  cannot  be 
reached  with  the  above  described  forceps,  the  object  is 
sometimes  best  attained  by  means  of  the  root-screw.  A 
large  nund)er  of  screws  of  various  thickness  exist,  but  one 
which  corresponds  in  diameter  to  that  of  all  root  canals 
is  sufficient  for  most  cases.  It  is  screwed  to  the  accom- 
panying handle,  and  is  then  inserted  into  the  root  canal, 
which  is  usually  enlarged.  A  lateral  and  outward  move- 
ment is  usually  sufficient  to  remove  the  roots.  If,  how- 
ever, the  root  on  the  liugual  side  is  deeply  destroyed, 
while  the  labial  side  rises  beyond  the  alveolar  border,  a 
Langenbcck's  periosteal  elevator  should  be  resorted  to. 
The  application  of  this  instrument  is  shown  in  Fig.  149. 


308 


EXTRACTION  OF  TEETH. 


It  is  a  very  simple  tool,  the  end  of  which  is  concave  and 
forms  an  obtuse  angle  with  the  handle,  which  is  thick  and 
made  of  wood.  This  handle  is  tightly  grasped  by  the 
whole  hand,  the  concave  point  is  forced  along  the  neck 
of  the  tooth  until  the  alveolus  is  reached,  and  the  root  is 
then  forced  with  considerable  pressure  toward  the  oral 
cavity.  What  was  said  of  the  upper  roots  is  also  true  of 
the  lower. 


Fig.  149.— The  application  of  the  Langenbeck  periosteal  elevator. 

The  same  forceps  are  employed  in  uncomplicated  cases 
as  for  the  loioer  hiGisor  teeth.  They  may  even  be  used  to 
extract  molar  roots  which  are  united.  The  root  which 
extends  above  the  alveolus  is  the  one  to  be  grasped,  for 
then  we  often  have  the  satisfaction  of  seeing  the  others 
coming  with  it.  The  resection  forceps  are  not  of  much 
service  in  the  posterior  and  thicker  portions  of  the  jaw. 
Therefore,  it  is  better  in  hopeless  cases,  to  cut  through 
the  alveolar  process  from  both  sides  above  the  affected 
part  with  the  alveolar  forceps.  It  must  not  be  forgotten 
when  the  Langenbeck  periosteal  elevator  is  employed, 
that  the  lower  jaw  must  be  steadied  with  the  hand  so 
that  it  will  not  slip  or  become  dislocated. 


EXTRACTION  OF  DECIDUOUS  TEETH.  309 


EXTRACTION  OF  DECIDUOUS  TEETH. 

The  primary  teeth  are  very  rarely  extracted  in  a  well 
regulated  practice.  Premature  extraction  causes  the 
alveolus  to  atrophy,  so  that  the  permanent  teeth  fail  to 
find  sufficient  space  ;  and,  furthermore,  the  teeth  of  second 
dentition  require  for  their  healthy  development,  the  pres- 
sure stimulus  which  mastication  exerts  upon  the  first 
teeth.  On  these  grounds  the  deciduous  teeth  should  be 
fostered  as  carefully  as  the  permanent.  Therefore,  only 
such  teeth  are  usually  extracted  whose  roots  are  under- 
going absorption,  and  whose  sharp  edges  and  points  irritate 
the  surrounding;  tissues.  As  most  of  such  teeth  are 
loose,  they  may  be  removed  without  difficulty.  Similar 
forceps  are  employed  as  for  the  permanent  teeth,  only 
smaller  in  size.  If  it  is  necessary  to  extract  deciduous 
teeth  which  are  not  loose,  it  must  not  be  forgotten  that 
they  are  set  in  a  very  flexible  jaw  and  possess  compara- 
tively weak  roots  ;  there  is,  therefore,  no  need  of  apply- 
ing the  forceps  with  great  strength  and  to  luxate  as 
energetically  as  in  the  case  of  the  permanent  teeth.  How- 
ever, the  operation  must  not  be  looked  upon  as  being  too 
easy,  for  when  the  crown  instead  of  the  neck  of  the  tooth 
is  grasped,  a  fracture  may  result,  an  accident  which  will  not 
tend  to  give  confidence  to  the  already  frightened  children. 

In  conclusion  the  writer  wishes  to  call  attention  to  a 
moral  })()int  which  is  often. sinned  against ;  namely,  that 
in  case  it  is  intended  to  remove  the  tooth  of  a  child, 
quietly  to  make  your  intention  known,  and  never  to 
deceive  the  patient.  Often  even  the  parents  implore  us 
not  to  tell  the  child  tlie  truth ;  if  we  were  to  accede  to 
these  requests,  it  would  be  but  our  just  reward  if  future 
clients  were  to  show  a  lack  of  confidence  and  respect. 

COMPLICATIONS  DURING  AND  AFTER  EXTRACTION. 

An  extraction  is  not  always  performed  without  ill 
results,  for  unpleasant  aceulcitfs  may  occur  which  involve 
either  the  tooth  itself  or  the  surrounding  structures. 


310  EXTRACTION  OF  TEETH. 

The  most  frequent  accident  is  fracture  of  the  tooth  to  be 
extracted.  The  awkwardness  of  the  operator  is  often  the 
cause.  He  either  selects  poorly  fitting  forceps  or  he 
applies  them  improperly.  Frequently  the  tooth  is  too 
forcibly  luxated,  or  it  is  grasped  too  tightly.  In  the 
majority  of  cases,  however,  the  dentist  cannot  be  blamed 
for  the  accident.  This  is  especially  true  of  those  cases 
in  which  the  patient  behaves  unreasonably,  draws  the 
head  to  one  side,  and  strikes  at  the  forceps.  Sometimes, 
however,  teeth  break  oif  most  unexpectedly  without  the 
dentist  or  patient  being  at  fault,  as  when  the  alveolus  is 
exceptionally  hard  and  non-yielding,  and  when  the  teeth 
are  as  brittle  as  glass.  Also,  other  factors  occur,  such  as 
anomalies  in  construction,  and  in  the  course  of  the  roots, 
and  the  like. 

If  the  tooth  to  be  extracted  is  not  properly  grasped, 
the  forceps  may  act  upon  a  neighboring  tooth  and  thus 
loosen  it  or  it  may  even  be  fractured  or  knocked  out. 
Such  loosened  teeth  should  be  left  alone  or  at  the  most  be 
fastened  with  a  ligature,  and  in  about  fourteen  days  they 
again  grow  fast.  Aside  from  the  neighboring  teeth  the 
antagonistic  teeth  also  run  a  certain  risk  of  being  frac- 
tured. This  happens  when  the  tooth  leaves  its  alveolus 
with  unexpected  ease,  on  account  of  which  the  forceps 
easily  strike  the  teeth  of  the  opposite  row. 

Kot  unfrequently  a  fine  long  bony  plate  is  attached  to 
the  roots  of  the  extracted  tooth,  especially  when  the  upper 
molars  are  removed.  This  is  of  no  significance,  but  if 
longer  portions  of  the  alveolar  process  break  ofP  the  con- 
dition may  be  considered  a  complication.  The  tooth-cell 
portion  of  the  alveolar  process  of  the  lower  jaw,  especiall}' 
in  the  region  of  the  molars,  is  most  likely  to  become 
fractured,  because  it  is  brittle  and  unyielding  in  that 
neighborhood.  Formerly,  when  the  dental  key  was 
employed,  this  complication  occurred  much  more  fre- 
quently. Fractures  in  the  upper  jaic  near  the  molars  may 
expose  the  antrum  of  Highmore.  They  usually  heal  of 
their  own  accord  when  proper  cleanliness  of  the  oral 
cavity  is  maintained.     Sometimes^  however,  it  may  lead 


COMPLICATIONS  DURING  EXTRACTION.        311 

to  suppuration,  and  finally  to  the  formation  of  the  empy- 
ema, which  eventually  becomes  chronic. 

A  very  unpleasant  complication  consists  in  bruising  and 
leaving  of  the  surrounding  soft  parts,  such  as  the  gums, 
the  lips  and  the  tongue. 

An  extensive  tearing  of  the  gums  occurs  at  times  and 
may  require  a  suture.  Much  more  serious  are  bruises  of 
the  periosteum,  which  lead  to  necrosis  of  the  bones. 

Intense  loound  pains  frequently  follow  extraction, 
although  they  occur  rarely  after  other  operations.  They 
either  represent  the  continuation  of  the  extraction  pain, 
which  may  continue  for  hours  or  even  days,  or  they  are 
intermittent  and  equally  as  severe,  but  set  in  only  after 
the  elapse  of  some  time.  Sometimes  the  pain  is  localized 
in  the  tooth-socket,  but  more  often  it  spreads  over  an 
extensive  area  of  the  face.  It  exists  largely  in  the  region 
of  the  branches  of  the  trigeminal  nerve,  and  therefore 
simulates  neuralgia. 

The  cause  may  sometimes  be  looked  for  in  the  tearing 
and  twisting  of  the  nerves  which  lead  to  the  pulp ; 
but  devitalized  teeth  also  give  rise  to  such  symptoms,  and, 
in  such  cases,  it  is  more  likely  that  the  cause  is  the 
tearing  of  the  nerves  of  the  periosteum.  Pain  in  the 
tooth-sockets  occurs  more  often  in  the  lower  than  in 
the  upper  teeth,  which  is  accounted  for  by  the  fact 
that  the  mandibular  nerve,  which  is  imbedded  in  the 
spongiosa,  directly  underneath  the  roots  of  the  molars, 
becomes  bruised  during  luxation  by  destruction  of  the 
bony  trabeculse.  Secondly,  infectious  processes  are  more 
prone  to  develop  in  the  lower  jaw  for  mechanical 
reasons,  than  they  do  in  the  up{)cr  jaw.  When  the  pains 
do  not  appear  until  much  later,  we  should  take  into 
consideration  the  factor  described  by  Saner,  according 
to  which  the  periosteum  and  the  gums,  because  of 
scar  formation,  lie  over  sharp  edges,  which  cut  into 
the  soft  tissue. 

Wound  pains  should  be  treated  energetically,  for, 
as  may  be  observed,  the  after-pain,  from  extracting, 
is  very  severe.     In  light  cases,  washing  with  chamomilla 


312  EXTRACTION  OF  TEETH. 

tea  suffices.  Frequently,  on  the  contrary,  tlie  cold 
application  is  much  more  efficient,  and  is  done  by  simply 
spraying  cold  water  into  the  part.  Internally,  antipyrin 
(J  5  gr.  to  1^3  a  day),  or  phenacetin  (15-45  gr.)  are 
administered.  Chloral  hydrate  (15  gr.-45  gr.)  is  em- 
ployed as  a  hypnotic,  and,  locally,  a  tampon  is  inserted 
into  the  alveolus.  This  tampon,  which  is  composed 
of  clean  cotton,  is  previously  immersed  in  a  5  per  cent, 
solution  each  of  cocain  and  iodoform.  This  application 
must  be  repeated  until  all  pain  disappears.  If  all  of 
these  remedies  fail,  we  may  resort  to  morphin,  of  which 
a  solution,  containing  ^  gr.,  is  injected  into  the  gum  of  the 
affected  side. 

A  serious  complication,  at  times,  is  the  development 
of  hemorrhages  after  extraction.  This  is  not  only 
observed  in  hemophilia,  for  large  hemorrhages  occur  in 
certain  diseased  conditions,  but  without  any  known 
cause. 

Such  hemorrhages  are  most  successfully  combated  with 
the  ordinary  styj^tics,  such  as  alum  and  sesquichlorate  of 
iron,  by  means  of  hot  water  (according  to  J.  Scheff)  or 
adrenalin  chlorid.  If  the  hemorrhage  cannot  be  stopped 
by  such  means,  Ave  must  resort  to  mechanical  closure 
of  the  alveolus.  A\  e  must  realize  in  this  connection  that 
au  uncontrollable  hemorrhage  may  follow,  not  only  from 
the  blood  vessels  in  the  fundus,  but  also  from  many 
points  in  the  alveolus.  Therefore,  the  plug  must  be 
so  formed  that  the  whole  alveolus  is  tightly  closed 
to  its  very  summit.  For  this  purpose,  cotton  serves 
as  an  excellent  plugging  material.  It  should  be  first 
immersed  in  chlorid  of  iron,  and  then  dried.  The 
cotton  should  be  tightly  plugged  into  the  alveolus, 
and  be  allowed  to  remain  there  until  it  falls  out  of 
its  own  accord. 

In  obstinate  cases,  plugging  the  alveolus  with  a  very  hard 
substance  is  more  eflPectual ;  for  example.  Stent's  material  or 
guttapercha,  which  are  introduced  into  the  alveolus 
in  a  softened  state,  and  there  allowed  to  harden.  Plaster 
of  Paris   is   also   useful,  but   we  must  be  careful  that 


ANESTHESIA.  313 

this  substance  fills  the  whole  alveolus.  Another  method 
is  to  cut  a  cork  into  the  shape  of  the  alveolus,  and  insert 
it  into  place,  so  that  it  stands  far  enough  above  the  teeth 
to  permit  the  antagonizing  teeth  to  bite  upon,  and  force  it 
deeply  into  the  alveolus.  Patients  treated  in  this  way 
must  not,  however,  open  the  mouth,  for  otherwise 
the  hemorrhage  will  begin  anew, 

Xiemeyer  has  constructed  an  apparatus  for  this 
complication,  consisting  of  a  metallic  plate  which 
fits  exactly  over  the  alveolus,  and  which  is  fixed  with 
two  clamps  to  the  neighboring  teeth.  In  that  manner, 
the  alveolus  is  tightly  closed  with  a  covering,  which 
prevents  the  escape  of  blood,  and  which  does  not  inter- 
fere with  opening  of  the  mouth.  Since  neglect  of  these 
post-operative  hemorrhages  leads  to  considerable  loss 
of  strength,  and  even  death,  the  patient  should  not  be 
discharged  until  the  blood  has  ceased  to  flow,  and  he 
should  be  advised  to  seek  our  assistance  if  hemorrhage 
reappears  later. 

ANESTHESIA. 

Dental  operations,  especially  extraction  of  teeth,  are 
frequently  very  painful,  and,  therefore,  we  are  compelled, 
in  nervous  and  sensitive  patients,  to  resort  to  pain- 
alleviating  or  pain-destroying  remedies. 

The  action  of  such  anesthetics  is  limited,  either  to 
the  ]>art  being  operated  upon  (local  anesthesia),  or  to 
the  whole  body  (narcosis). 

Local  anesthesia  may  be  produced  by  thermic  action 
(cold),  mechanical  action  (swelling  of  the  nerve  fibers 
and  pressure  upon  the  same),  and  by  chemical  action. 

Anesthesia  by  means  of  cold  is  best  obtained  with 
evaporating  substances,  such  as  ethyl  chlorid  (chlorethyl), 
which  finds  its  greatest  field  of  usefulness  in  dentistry. 
Before  applying  ethyl  chlorid,  the  neighborhood  of 
the  tooth  to  be  extracted  should  be  protected,  so  that 
it  will  not  be  affected  by  this  liquid.  This  is  done 
by  covering  the  neighboring  teeth  with  a  layer  of  softened 
wax,  cotton   rolls,  or  a  napkin.     The  commercial  ethyl 


314  ANESTHESIA. 

chlorid,  which  is  obtained  in  tubes,  is  then  directed  both 
upon  the  labial  and  lingual  side  of  the  alveolus  of 
the  tooth  to  be  extracted.  Since  ethyl  chlorid  boils 
at  11°  C,  the  tube  may  be  held  quite  some  distance 
from  the  field  of  operation,  for  the  heat  of  the  hand 
is  sufficient  to  cause  the  expansion  of  this  prepara- 
tion, and  to  force  a  strong  stream  to  be  sprayed  forth. 
After  the  spray  has  been  allowed  to  act  upon  the  gum 
for  from  ten  to  fifteen  seconds,  a  shiny  white  coating 
of  frost  is  formed,  which  indicates  that  the  operation 
may  be  begun.  The  latter  is  thus  made  decidedly 
more  bearable,  and,  especially  so,  if  in  association  with 
the  local  action  of  cold,  a  light  general  anesthesia  is 
produced  by  inhalation  of  gas.  Ethyl  chlorid  is  also 
recommended  for  minor  operations  upon  the  mouth,  such 
as  removals  of  growths,  etc.  It  is  sometimes  also  of 
good  service  in  the  extraction  of  a  living  pulp,  in  which 
case  the  spray  is  directed,  not  upon  the  gum,  but  upon 
the  pulp.  It  must  be  remembered  in  this  connection,  on 
account  of  the  highly  inflammable  nature  of  this  substance, 
that  it  be  not  followed  by  the  application  of  the  thermo- 
cautery. The  consequences  of  such  a  mistake  are 
illustrated  by  the  following  case  :  "  When  this  method 
was  still  new,  the  writer  wished  to  burn  away  an  epulis 
frozen  in  the  above  manner.  As  the  oral  cavity  was 
approached  with  the  red-hot  cautery,  a  flame  blazed  forth 
from  it.  Luckily,  no  burn-wounds  developed,  and,  aside 
from  the  shock,  there  were  no  ill  effects." 

Anesthesia  is  obtained  by  mechanical  action  througli 
the  injection  into  the  tissue,  under  high  pressure,  of  a 
very  dilute  solution  of  a  medicament  or  physiologic  salt 
solution.  This  is  supposed  to  cause  a  swelling  of  the 
nerve  fibres.  Such  fluids  must  be  injected  in  large  quan- 
tities, and  as  strong  pressure  is  preferable,  a  powerful 
syringe  should  be  employed.  The  injections  should  be 
made  in  two  or  three  different  areas,  on  both  the  lingual 
and  labial  side,  until  the  gum  swells  like  a  blister. 
Attempt,  also,  to  inject  some  of  the  fluid  between  the  root 
of  the  tooth  and  the  alveolus.  Many  of  these  agents,  which 


ANESTHESIA.  315 

may  be  had  on  the  market,  have  a  purely  mechanical 
action.  This  method  is  not  universally  employed,  for  at 
times  sensation  is  only  partially  obtuuded,  and  the  multi- 
ple deep  injections  are  painful. 

Of  chemicals  having  anesthetic  influence,  cocain  occupies 
the  first  position.  Whenever  it  comes  in  contact  with  a 
nerve  it  destroys  its  power  of  sensation  for  a  short  time. 
For  operations  upon  the  gum,  which  absorbs  this  medica- 
ment well,  it  suffices  to  paint  the  part  with  a  from  5  to 
20  per  cent,  solution,  and  allowing  it  to  act  from  two  to 
four  minutes.  As  this  analgesia  remains  local,  and  does 
not  penetrate  deeply,  it  suffices  for  small  incisions  into 
the  gums  but  not  for  extraction  of  the  teeth  ;  in  the  latter 
case  the  solution  should  be  injected  beneath  the  gum. 
Too  strongly  concentrated  solutions  should  be  interdicted 
for  they  may  cause  a  number  of  toxic  symptoms.  For 
that  reason  the  20  per  cent,  solution  of  cocain  recom- 
mended formerly  by  Ad.  Witzel  for  subgingival  appli- 
cation is  no  longer  employed  and  is  now  substituted  by 
much  weaker  solutions.  Schleich's  solution  which  con- 
tains but  a  small  percentage  of  cocain  is  a  favorite  prepa- 
ration of  many  dentists.  Thiesing  states  that  the  1  per 
cent,  solution  should  not  be  exceeded  and  that  not  more 
than  2g  (0.02  cocain)  be  given  to  a  single  dose  unless 
absolutely  necessary.  Especial  care  must  be  exercised  in 
administering  it  to  children.  Braun  recommends  the 
following  solution  : 

R 

Cocain  h yd rochl orate,  gr.  15  (1.0), 

Sodium  chlorate,  gr.  12  (0.8), 

Aq.  distill.                   qs.  ad  ^iii'A  (100.0). 
M.  D.  S.  1  per  cent,  cocain  solution. 

Following  is  the  teclmic  of  its  application :  If  the 
operative  field  should  be  anesthetized  for  the  purpo.se  of 
extracting  a  tooth,  a  20  per  cent,  solution  of  cocain  is  at 
first  painted  upon  the  gum,  which  has  been  previously 
well  dried  and  washed  off,  either  Avith  ether  or  hydrogen 
peroxid.  Next  the  gum,  which  has  been  made  less  sen- 
sitive, is  pierced  by  the  Pravaz  syringe,  which  is  filled 


316  ANESTHESTA. 

with  a  1  per  cent,  solution,  and  which,  of  course,  has  been 
thoroughly  sterilized.  The  needle  of  the  syringe  should 
penetrate  deeply  enough  to  prevent  the  fluid  from  again 
oozing  out  of  the  point  of  entrance. 

A  labial  and  a  lingual  injection  should  be  made,  and 
\  gram  of  solution  in  the  syringe  is  emptied  on  each  side. 
The  extraction  may  be  begun  after  three  minutes,  and 
usually  may  be  performed  without  any  pain  whatever. 
Only  in  the  case  of  periostitis  is  it  impossible  to  obtain 
complete  anesthesia. 

As  has  already  been  stated,  such  injections  are  not 
altogether  harmless,  and  therefore  a  number  of  substitutes 
have  been  oflPered  in  place  of  the  cocain. 

Beta-eucain,  which  has  been  strongly  recommended  in 
recent  years  by  Thiesing,  has  probably  been  used  the 
most  extensively.  According  to  that  authority,  it  has 
the  same  action  as  cocain  without  being  poisonous.  As 
a  further  advantage  over  cocain,  this  remedy  can  be 
sterilized  by  boiling  without  losing  any  of  its  properties. 
Depending  upon  the  nature  of  the  operation  (incision, 
extraction  of  loose  or  firm  teeth)  from  a  2  to  a  3  per  cent, 
solution  is  employed.     Following  is  the  prescription  : 

R 

Beta-eucain,  gr.  30.00  (2.0), 

Sodium  chlorate,  gr.    9.00  (0.6), 

Aq.  distill.  qs.  ad.  fgiii^  (100.0). 

M.  D.  S.  2  per  cent,  solution  of  eucain. 

The  quantity  of  the  fluid  should,  of  course,  be  measured 
according  to  the  severity  of  the  operation.  In  light  cases 
one-half  of  a  Pravaz  syringeful  is  sufficient,  but  in  case 
of  necessity  the  dose  may  be  increased  to  two  such 
syringefuls. 

In  order  to  obtain  good  results  with  beta-eucain  two 
subperiosteal  injections,  one  on  the  labial  and  the  other 
on  the  lingual  side,  should  be  made  for  the  extraction  of 
teeth  possessing  but  a  single  root.  In  the  case  of  the 
upper  molars,  corresponding  to  the  three  roots,  two  buccal 
and  one  lingual  injections  are  made.  Since  they  are 
imbedded  in  a  thick  bony  mass,  the  lower  molars  require 


DENTIN  ANESTHESIA. 


317 


the  largest  quantity  of  fluid  and  the  greatest  number  of 
injections.  The  solution  is  best  introduced  into  the  jaw- 
])one  in  this  case  by  means  of  four  injections,  of  which 
two  are  made  along  the  buccal  root  border  and  two  along 
the  lingual.  In  well-developed  jaws  an  attempt  may  be 
made  to  pass  the  needle  between  the  roots  and  the  alveoli, 
in  order  to  introduce  the  anesthetic  into  the  interior  of 


Fig.  150.— Pravaz  syringe. 

the  l)one.  For  this  purpose,  however,  the  needle  must 
not  be  forced  deeply  into  the  alveolar  periosteum  at  once, 
for  thus  too  much  pain  is  occasioned,  but  instead,  the 
needle  should  be  passed  slowly,  and  accompanied  at 
intervals  by  the  forcing  out  of  a  little  of  the  fluid.  The 
needle  is  then  gradually  forced  through  the  successively 
anesthetized  tissue. 

DENTIN  ANESTHESIA. 

One  of  the  most  important  problems  is  that  of  anesthe- 
tizing the  dentin.  We  need  not,  therefore,  be  surprised 
at  the  fact  that  new  remedies  and  methods  are  continually 
being  l^rought  forth,  which  arc  claimed  to  destroy  more 
or  less  completely  the  pain  accompanying  the  preparation- 
of  carious  tooth  cavities. 

Unfortunately,  none  of  these  remedies  have  been  worth 
adoption,  while  the  <n*di nary  local  anesthetics  are  particu- 
larly iiK'flPectual  for  tliis  ]>urpose,  probably  because  in 
place  of  nerves,  the  dentin  has  the  Tomes'  fibres,  which 


318  ANESTHESIA. 

assume  the  function  of  a  nerve  apparatus.  Furthermore, 
we  unfortunately  know  but  little  about  the  Tomes'  fibres, 
and  that  is  probably  the  reason  of  our  inability  to  influence 
them . 

The  majority  of  these  remedies  are  either  useless,  or  if 
they  are  really  successful  in  making  the  dentin  non-sensi- 
tive, they  inj  ure  the  pulp. 

The  sensitiveness  may  be  overcome  by  inserting  into 
the  cavity  for  several  days  zinc  chlorid,  creosote,  carholw 
acid,  or  pajrmionochlorjjhenol.  The  latter,  which  is  espe- 
cially useful,  was  recommended  by  Walkhoif.  Its  appli- 
cation is  as  simple  as  that  of  the  other  remedies,  and 
consists  in  introducing  into  the  tooth  cavity  a  pin-head 
sized  amount  of  the  crystallized  fluid.  The  cavity  is  then 
well  closed  because  of  the  caustic  action  of  this  remedy. 
Homer  obtains  a  marked  decrease  in  the  amount  of  pain 
associated  with  excavation  of  a  tooth  by  rubbing  a  bit  of 
chlorphenol  into  a  powder,  and  permitting  it  to  lie  in  the 
cavity  for  from  two  to  three  minutes. 

A  tooth  may  be  excavated  with  but  little  pain  by 
means  of  kataphoresis,  which  consists  in  conducting  low 
tension  electric  currents  through  the  tooth.  This  pro- 
cedure is,  however,  not  only  very  inconvenient  and  time 
consuming,  but  what  is  much  worse,  it  injures  the  pulp. 
It  has  been  repeatedly  noticed  that  teeth  treated  by  means 
of  kataphoresis  lose  their  vitality  either  immediately  or 
it  may  be  some  months  later. 

Momentary  action  is  probably  most  frequently  produced 
by  means  of  carbonic  acid,  which  owes  this  property  to 
its  action  upon  the  nervous  apparatus,  which  becomes 
fatigued  and  loses  its  conductivity.  This  action  is 
especially  marked  during  the  nascent  state.  Credit  is 
due  to  Walkhoff"  for  the  addition  of  this  remedy  to  our 
armamentarium.  By  means  of  an  apparatus  invented  by 
Bauchwitz  it  is  possible  to  obtain  the  action  of  carbonic 
acid  upon  the  dentin  in  a  simple  manner.  Whether  this 
remedy  will  continue  to  be  as  promising  in  the  future,  can 
only  be  determined  after  the  experiences  of  various  prac- 
titioners have  been  compared. 


GENERAL  ANESTHESIA.  319 

By  observing  a  physical  law,  patients  may  be  spared 
much  pain  ;  namely,  that  just  as  dull  instruments  in  opera- 
tions upon  the  soft  parts  cause  severer  pain  than  sharp 
instruments,  so  do  dull  dillls  act  upon  the  sensitive  dentin. 
Therefore,  we  should  employ  only  first  class  and  abso- 
lutely sharp  instruments,  and  the  cavity  must  be  kept 
dry  in  order  to  prevent  the  instrument  from  slipping 
against  the  walls. 

The  surest  action  is  obtained  by  submucous  or  sub- 
periosteal  injections  of  a  5-2  per  cent,  of  cocain  or 
betct-eucain  solution,  in  the  same  manner  as  for  extraction 
of  teeth.  The  operator  must,  however,  begin  work 
immediately,  for  the  anesthesia  which  is  sometimes  com- 
plete, lasts  only  five  to  ten  minutes ;  that  is,  about  from 
five  to  fifteen  minutes  after  injection. 

This  method  is  sometimes  rcAvarded  by  most  satisfactory 
results,  for  if  care  is  taken  to  anesthetize  the  gums  before 
making  the  injections,  the  patient  feels  no  pain  during  the 
whole  operation. 

GENERAL  ANESTHESIA. 

By  general  anesthesia  is  meant  that  condition  in  which 
the  sensorv  nerve  centers  cease  to  functionate,  as  contrasted 
with  local  anesthesia,  in  which  only  the  peripheral  sensory 
•  nerves  have  ceased  to  act.  To  obtain  unconsciousness, 
volatile  substances  are  employed  which  are  rapidly 
absorbed  by  the  blood  and  again  rapidly  discharged.  Such 
substances  are  nitrous  oxid,  ethyl  bromid,  chloroform,  and 
ether. 

Nitrous  oxid,  or  laughing  gas,  is  probably  most  fre- 
quently used  in  dental  operations.  It  is  a  colorless  gas 
of  a  sweetish  odor,  and  is  obtained  from  ammonium 
nitrate.  Before  using  it,  from  fifteen  to  twenty  litres  of 
this  gas,  Avhich  is  the  ([uantity  required  for  a  short  opera- 
tion, are  allowed  to  flow  into  a  gasometer,  the  receiver 
of  which  is  immersed  in  water.  The  patient  inhales  the 
gas  by  means  of  a  mask,  which  is  joined  to  the  gasometer 
by  a  rubber  tube.  This  mask  is  supplied  with  a  valve 
through  which  the  expired  air  escapes. 


320  ANESTHESIA. 

Complete  unconsciousness  results  in  about  one  to  two 
minutes ;  the  subject  awakens,  without  any  untoward 
effect,  of  his  own  accord,  and  usually  refers  to  the  pro- 
cedure as  very  agreeable.  Of  the  large  number  of 
patients  who  have  been  anesthetized  by  nitrous  oxid  only 
very  few  are  known  to  have  died  from  its  effects.  We 
may  conclude,  therefore,  that  this  form  of  narcosis  is  one 
of  the  safest.  It  is,  however,  only  indicated  for  opera- 
tions of  short  duration,  like  extraction  of  one  or  more 
teeth. 

In  more  recent  times,  in  spite  of  these  advantages  of 
nitrous  oxid,  it  has  fallen  more  and  more  into  disuse. 
The  reasons,  no  doubt,  are  simply  convenience  and 
economy.  The  modern  remedies  do  not  require  such 
complicated  apparatus. 

Ethyl  bromid  is  more  convenient  in  application,  because 
it  can  be  inhaled  from  the  ordinary  chloroform  mask.  In 
case  of  necessity  a  piece  of  cloth  sprinkled  with  ethyl 
bromid  serves  the  same  purpose. 

Since  ethyl  bromid  is  rapidly  decomposed  by  the  air, 
it  is  advisable  to  set  the  mask  tightly  upon  the  face,  and 
to  cover  it  with  a  rubber  sheet. 

The  amount  to  be  used  is  from  ten  to  thirty  grams, 
which  is  best  poured  upon  the  mask  at  one  time.  Nar- 
cosis develops  in  a  few  minutes  and  lasts  only  a  short 
time,  but,  by  adding  more  of  the  anesthetic,  the  narcosis 
may  be  prolonged  for  from  ten  to  fifteen  minutes.  Narcosis 
for  a  longer  period  of  time  is  unsafe. 

As  the  corneal  reflex  is  not  obliterated,  we  determine 
by  another  sign  whether  unconsciousness  has  set  in  ;  this 
consists  in  the  fact  that  the  raised  arm  falls  powerless 
when  narcosis  has  developed.  Some  prefer  to  have  the 
patient  count  aloud;  this  is,  however,  not  very  satisfactory, 
for  it  is  interfered  with  by  the  speculum  which  is  placed 
into  the  mouth  before  narcosis. 

During  th^  narcosis  the  patient  is  wholly  unconscious, 
notwithstanding  that  the  muscles  still  respond  to  stimuli, 
and  in  spite  of  the  fact  that  at  the  moment  of  extraction 
the  patient  cries  out  loudly. 


GENERAL  ANESTHESIA.  S2l 

The  awakening  is  usually  abrupt  and  like  that  follow- 
ing healthy  sleep.  Xausea  occurs  only  in  very  rare  cases. 
The  patient  describes  the  process  of  narcotization  as  a 
disturbed  dream,  in  which  he  continually  hears  the  tele- 
phone ringing,  or  the  noise  of  the  tram  car,  or  may  imagine 
he  is  taking^  a  ride  in  a  railway  train. 

At  the  commencement  of  the  narcosis  the  respiration 
is  often  irregular,  and  the  patients  should  therefore,  be 
advised  to  take  deep  and  slow  respirations.  Later,  how- 
ever, the  respiration  again  becomes  normal,  and  in  deep 
narcosis  snoring  is  often  heard.  Blood  pressure  and  pulse 
rate  remain  normal.  During  the  excitement  at  the 
beginning  of  the  narcosis  the  frequency  of  the  pulse 
increases  (it  may  rise  to  one  hundred  and  tifty  beats  a 
minute),  but  when  the  stage  of  unconsciousness  sets  in 
the  heart  action  returns  to  normal. 

Ethyl  bromid  is  excreted  chiefly  through  the  lungs, 
and  small  amounts  through  the  urine.  The  breath  has 
an  unpleasant  garlic-like  odor  for  from  two  to  three  days 
after  the  anesthetization. 

Schneider,  b}'  means  of  animal  experimentation,  proved 
that  ethyl  bromid  is  no  cardiac  poison.  The  blood-pres- 
sure fall  was  l^arely  preceptible  after  the  largest  dose,  and 
the  animals  died  in  every  case  from  asphyxia  and  never 
from  syncope.  For  prolonged  narcosis  ether  or  ehloro- 
form  are  more  suitable. 

The  latter  is  especially  serviceable  in  dental  practice, 
because  the  narcosis  continues  for  some  time  after  removal 
of  the  mask.  Since  effective  quantities  of  chloroform  are 
more  dangerous  than  the  first  two  mentioned  substances, 
it  is  advisable  to  secure  the  service  of  a  skilled  colleague 
to  administer  the  anesthetic. 

To  prevent  accidents  during  and  after  the  narcosis,  the 
folloM'ing  fundamental  laws  should  1)0  observed.  They 
hold  true  for  all  anesthetics,  whether  etliyl  In'omid,  nitrous 
ox  id  or  chloroform. 

The  anesthetic  must  be   fresh   and   absolutely   clean. 
Ethyl  bromid  and  chloroform  must  be  kept  in  dark  bottles, 
for  light  decomposes  them. 
21 


322  ANESTHESIA. 

The  heart  must  be  carefully  examined  before  the  opera- 
tion ;  if  a  serious  form  of  heart  disease  exists,  narcosis  is 
contraindicated,  and,  if  it  cannot  be  avoided,  only  ether 
is  permissible. 

Artificial  teeth  must  be  removed  lest  they  fall  into  the 
larynx. 

Tight  clothing  which  interferes  with  respiration  (collars, 
corsets,  etc.)  must  be  loosened  or  removed. 

During  anesthetization  the  operator  must  not  lose  sight 
of  the  patient  for  a  moment.  He  must  constantly  watch 
the  pulse,  the  respiration,  the  appearance  of  the  patient, 
and  eventually  the  reflexes. 

If  the  pulse  becomes  irregular,  the  color  of  the  face 
pale  or  dark  red,  and  the  breathing  should  cease,  etc.,  the 
anesthetic  must  be  removed  immediately.  The  tongue, 
which  has  fallen  back  is  rapidly  drawn  forward,  and  arti- 
ficial respiration  instituted. 

The  vapor  of  the  anesthetic  must  not  be  too  concen- 
trated, but  must  always  be  mixed  with  some  air,  and 
immediately  after  the  operation  the  air  in  the  room  must 
be  renewed. 

It  is  recommended  by  many  that  in  the  case  of  collapse, 
the  patient  should  inhale  amyl  nitrite,  or  receive  sub- 
cutaneous injections  of  camphor  and  ether.  Better  than 
these  artificial  stimuli  is  the  mechanical  assistance 
obtained  by  stretching  the  patient  out  flat,  so  that  the 
blood  flows  to  the  brain,  and  then  energetically  practicing 
artificial  respiration. 

In  conclusion,  we  wish  to  particularly  advise  that  anes- 
thetization be  never  instituted  with  out  professional  assist- 
ance, for,  aside  from  the  fact  that  frequent  erotic  dreams, 
in  which  the  unconscious  patient  imagines  she  was  ruined, 
have  led  to  penal  law  suits,  an  assistant  is  also  required 
for  the  institution  of  artificial  respiration. 

By  fulfilling  all  of  these  requirements,  one  may  have  a 
clean  conscience  if  an  accidenthappens,  and  also  the  even- 
tual resulting  legal  decision  will  not  be  unfavorable. 


MOUTH  PREPARATION  FOR  ARTIFICIAL   TEETH.    323 

PREPARATION  OF  THE  MOUTH   FOR 
ARTIFICIAL    TEETH. 

The  loss  of  teeth  leads  to  an  interference  with  mastica- 
tion and  to  weak  digestion.  A  large  number  of  gastric 
diseases  may  be  traced  to  this  condition.  If  the  lost  teeth 
are  replaced  by  artificial  ones,  the  general  health  of  the 
patient  shows  a  remarkable  improvement  in  a  surprisingly 
short  time.  We  may,  therefore,  conclude  that  artificial 
teeth  are  capable,  from  a  physiologic  point  of  view,  of 
replacing  natural  teeth.  The  same  holds  true  of  articula- 
tion, as  well  as  of  appearance  in  deficiency  of  the  front 
teeth. 

According  to  the  condition  of  the  oral  cavity,  more  or 
less  preparatory  treatment  of  the  mouth  is  required.  The 
object  of  such  treatment  is  to  establish  conditions  which 
will  favor  long  use  of  the  artifical  teeth.  Therefore,  all 
carious  teeth,  if  any  are  present,  must  be  filled.  Reaction- 
less  roots,  which  occupy  an  awkward  position,  and  which 
are  suffering  from  periosteal  disease,  should  be  extracted. 
Since,  after  extraction  of  the  tooth,  the  portion  of  the 
alveolus  concerned  shrinks,  it  is  advisable  not  to  insert 
the  artificial  substitutes  until  after  the  elapse  of  some 


Fig.  151.— Simple  nippers. 


time  ;  that  is,  from  two  to  three  months,  or  even  a  longer 
time.  If,  for  some  important  reason,  this  postponement 
is  not  possible,  then  apply  a  provisional  set  of  teeth, 
which  should  be  rephiccd  by  a  permanent  set  in  the  space 
of  from  four  to  six  months. 


324  MOUTH  PBEPAEATION  FOB  ARTIFICIAL    TEETH. 

Protruding  portions  of  roots,  which  for  any  reason  we 
may  decide  not  to  extract,  are  removed  with  a  pair 
of  nippers  (Fig.  151  illustrates  the  simplest  form),  or 
with  root  forceps  and  small  stones  in  the  dental  engine. 


Fig.  152. — Cast  of  the  lower  jaw  made  with  Stent's  material. 

For  the  success  of  the  prosthesis,  a  proper  cast  is 
important.  For  obtaining  such  a  model,  a  specially 
formed  impression-tray  is  employed,  which  is  filled  with 


MOUTH  PttEPAUATION  FOR  ARTIFICIAL  TEETH.    325 

a  plastic  material.  The  tray  or  cup  filled  in  this  manner 
is  then  placed  into  the  mouth,  and  pressed  against 
the  alveolar  process  until  the  impression  material  has 
stiifened. 

The  materials  usually  employed  are  plaster  of  Paris, 
and  preparations  of  Stent,  Ash,  etc. 

Plaster  of  Paris  is  particularly  adaptable  in  toothless 
jaws,  but  if  teeth  are  present,  this  material  is  removed 
with  difficulty  after  it  is  once  hardened,  because  of  its 
hard  and  unyieldy  nature.  However,  because  of  these 
properties,  such  impressions  or  casts  are  very  exact,  and 
far  more  preferable  in  certain  cases  than  casts  made  from 
a  substance  of~  softer  consistency.  In  order  that  the 
])laster  of  Paris  may  rapidly  harden,  it  is  stirred  in  warm 
water,  to  which  a  little  salt  has  been  added ;  as  soon  as  it 
lias  assumed  the  consistency  of  gruel,  it  is  ready  for 
the  impression.  Care  must  be  taken  not  to  place  too 
much  of  this  material  in  the  tray,  for,  otherwise  it  may 
flow  into  the  pharynx,  nnd  excite  coughing  and  vomiting, 
both  of  which  interfere  with  obtaining  a  proper 
impression.  The  plaster  of  Paris  may  also  be  prevented 
from  flowing  backward  by  inclining  the  head  forward. 
The  impression  must  not  be  removed  from  the  mouth 
until  the  plaster  of  Paris  is  thoroughly  hardened,  which 
i-equires  several  minutes. 

Stenfs  composition  is  particularly  useful  for  jaws  which 
still  contain  teeth,  for,  without  distorting  the  cast, 
it  yields  sufficiently  to  alknv  of  its  removal.  This 
substance  is  softened  in  warm  water,  and  the  resulting 
mass  is  placed  into  the  tray  in  such  a  manner  that  it  will 
have  a  smooth  surface.  Cold  water  is  then  allowed 
to  flow  over  the  tray,  in  order  that  the  mass  may  stiffen 
rai)idly,  and  also  ]ireveut  injury  to  the  mucous  membrane 
from  the  heat.  Next,  the  mass  is  rapidly  passed  through 
a  flame,  which  makes  it  soft  and  easily  impressionable. 
The  impression-tray  is  introduced  into  the  mouth  in 
the  same  way  as  was  described  for  plaster  of  Paris. 
After  it  has  been  placed  into  its  proper  position  in 
the  mouth,   it  is  fixed  upon  the  alveolar  process  with 


326  MOUTH  PREPARATION  FOR  ARTIFICIAL  TEETH. 

uniform  pressure,  until  the  mass  has  hardened.  Fig.  152 
shows  exactly  how  the  details  are  reproduced  in  a  Stent's 
impression. 

A  discussion  of  the  way  in  which  the  model  is  prepared 
from  such  an  impression,  and  in  what  manner  the 
prosthesis  is  produced,  does  not  belong  here,  as  has 
already  been  stated  in  the  Preface,  but  rather  in  a 
text-book  on  technic. 


INDEX 


Aberration  of  tooth  band,  176 
Abrasions,  195,  197 

treatment  of,  197 
Abscess,  132 

apical,  of  root-membiune,  286 

blind,  289 

formation  on  lingual  side,  289 

interradicular,  286 

maxillary,  extraction  in,  296 

of  pulp,  272 

subperiosteal,  double-sided,  289 
Absence  of  teeth,  22 

partial,  of  enamel  covering,  193 
Absorption  of  alveolar  process,  37 
Accidents  in  extraction,  309 
Acid,  arseuious,  in  destroying  pulp, 
277  _ 

carbolic,  anesthesia  with,  318 

carbonic,  108 

anesthesia  by,  318 

conversion  of  sugar  into,  by  bac- 
teria, 106,  107 

in  cause  of  caries,  207 

lactic,  107 

ethylidene,  107 

tannic,  in  destroying  pulp,  278 
Actinomyces  bovis,  112 
staining  of,  112 

kernels,  120 
Actinomycosis  bovis,  119 
prognosis,  120 
symptoms,  120 
treatment,  120 
Adaraantoma,  148 
Adenocarcinoma  of  mouth,  143 
Adenoid  growths  of  pharynx,  effect 

on  teeth,  174 
Air  syringe  for  drying  cavities,  235 
Albuminoid     dissolving     ferment,  I 

105  I 


Alveolar  arches,  41 

arteries,  anterior  superior,  49 
superior  posterior,  49 

caries,  specific,  122 

ligament,  81 

nerves,  anterior,  50 

perforating  branches  of  interal- 
veolar  rami,  48 

periosteum,  56 

process,  41 

absoi-ption  of,  37 
fractures  of,  152 
lower  border  of,  43 
of  upper  jaw,  49 

pyorrhea,  122.     See   also   Pyor- 
rhea, alveolar. 
Amalgam  and  cement  filling,  com- 
bination of,  224 

copper-,  filling  with,  222 

filling,  222,  2o2 
Ameloblasts,  87 
Amputation  of  pulp,  281 
Anastomotic  canal  system  of  teeth, 

53 
Anesthesia,  313 

beta-eucain,  316,  319 

by  means  of  cold,  313 

carbolic  acid,  318 

carbonic  acid,  318 

chlorethvl,  313 

chlorofoi-m,  321,  322 

cocain,  315,  319 

creosote,  318 

dentin,  317 

ether,  321,  322 

ethvl  bromid,  320 
chlorid,  313 

general,  319 

kataphoresis  for,  318 

laughing  gas,  319 

327 


328 


INDEX 


Anesthesia,  local,  313 
nitrous  oxid,  319 
paramonochlorphenol,  318 
salt  solution  for,  314 
Schleich's  solution,  315 
zinc  chlorid,  318 
Anisodontous  teeth,  22 
Anomalies  in  position  of  teeth,  179 
treatment,  186 
of  form  in  individual  teeth,  177 
of  teeth,  174 

and  jaws,  174 
of  whole  tooth  row,  184 
treatment,  189 
Anterior  alveolar  nerves,  50 

superior  alveolar  arteries,  49 
Antrum  of  Highmore,  41 

empyema    of,   155.     See  also 
Empyema  of  antrum  of  High- 
more. 
Aperture,  pyriform,  42 
Aphthous  stomatitis,  117 

treatment  of,  118 
Apical  abscess  of  root-membrane, 
286 
foramina,  79 
Approximal  surface  of  tooth,  55 
Arch,  alveolar,  41 

branchial,  in  embryo,  165 
faucial,  in  embryo,  165 
palatine,  34 
Arcus  palatoglossus,  37 
palatopharyngeus,  37 
supramaxillaris,  50 
Arsenic  in  destroying  pulp,  277 
Arsenious  acid  in  destroving  pulp, 

277 
Arteries,  alveolar,   anterior    supe- 
rior, 49 
superior  posterior,  49 
infraorbital,  49 
maxillary,  internal,  48 
of  floor  of  mouth,  40 
of  oral  cavity,  37 
palatine,  greater,  37 
ranine,  40 
Articular  tubercle,  45 
Articulations  of  teeth,  65 
Artificial  teeth,  cast  of  mouth  for, 
324-326 
preparation  of  mouth  for,  323 


Atresia  of  root-canal,  280 
Atrophia  alveolaris  prsecox,  125 

treatment  of,  125 
Atrophy,  reticular,  of  pulp,  273 
Auditory  organ  in  embryo,  165 

Bacilli,  112 

gangrense  puljJEe,  268 

of  diphtheria,  112 
staining  of,  112 

of  influenza,  111 
staining  of,  111 

prodigiosus,  106 

pulpse  pyogenes,  106 

tubercle,  110 
staining  of,  110 
Ziehl-Neelsen  stain  for.  111 
Bacteria,  activity  of,  106 

black  pigments  from,  106 

brown  pigments  from,  106 

chemical  action  of,  104 

conversion  of  sugar  into  acid  by, 
106,  107 

gases  from,  107,  108 

metabolic  products  of,  105 

of  oral  cavity,  102 

pathogenic  action  of,  109 

peptonizing  activity  of,  199 

pigments  from,  106 

putrefaction  from,  107 
Bacterial  ferments,  105 
action  of,  105 
diastatic,  105 
Bacteriology,  102 
Balloon,    elastic,    in    cleft    palate, 

174 
Band,  enamel,  82 

tooth-,  82 
Bartholin,  duct  of,  39 
Bayonet-shaped  forceps,  307 
Beta-eucain  anesthesia,  316,  319 
Bicuspids,  58 

lower,  58 

extraction  of,  305 

permanent,  eruption  of,  100,  101 

upper,  58 

extraction  of,  303 
Biology  of  schizomycetes,  103 
Black  deposits,  191 

pigments  from  bacteria,  106 
Blind  abscess,  289 


INDEX 


329 


Blood-vessels  of  pulp,  80 

of  teeth,  48 
Bony  plate,  necrosis  of,  157 
Bowl-shaped  lacunse,  193 
Brachyodont  teeth,  22 
Branchial  arches  in  embryo,  165 
Bridge,  connective,  84 
Brown  deposits,  191 

pigments  from  bacteria,  106 
Buccal  surface  of  teeth,  55 

defects  of,  201 
Bunodont  teeth,  24 
Bui-s  for  dental  engine,  235 
Biirzel,  169 

Calcareous  concretions  in  pulp, 

81 
Calcification  of  deciduous  teeth,  89 

of  permanent  teeth,  99 
Calcium  granules  of  pulp,  273 
Canal,  mandibular,  45 
Canalis  incisivus,  43 
Cancroid  of  mouth,  143 
Cancrum  oris,  115,  121 
Canine  fossa,  41 

muscle,  41 

teeth,  57 
Cap,  application  to  pulp,  276 
Carbolic  acid  anesthesia,  318 
Carbonic  acid,  108 
anesthesia,  318 
Carcinoma  of  cheeks,  144,  145 

of  floor  of  moutli,  144,  145 

of  gums,  144,  146 

of  lips,  144 
prognosis,  144 
treatment,  145 

of  mouth,  142 

of  palate,  144,  145 

of  tongue,  144,  145 

scirrhous,  of  lips,  144 
Caries,  201 

acids  in  cause  of,  207 

alveolaris  specifica,  122 

approximal,  237 

areas  of  predilection  of,  202 

central,  237 

cervical,  237 

chemical  theory  of,  205,  210 

chemicoparasitic  theory  of,  206 

etiology  of,  293 


Caries,  extraction  in,  294 
frequency  of,  201,  202 
incipient,  201 
infusorise  in  cause  of,  205 
labial,  237 

leptothrixbuccalis  in  cause  of,207 
media,  238 
of  cementum,  214 
of  dentin,  212 

microscopic  detection  of,  213 
of  enamel,  microscopic  detection 
of,  212 
objective  symptoms,  211 
pigmentation  in,  211,  212 
parasitic  theory  of,  204,  210 
penetrating,  213 
pigmentation  in,  211 
predilection  areas  of,  237 
predisposing  influences  of,  203 
profunda,  238 
prophylaxis  of,  216 
protococcus  dentalis  in  cause  of 

205 
silver  nitrate  in,  219 
streptococci  in,  207 
superficial,  237 
treatment  of,  216,  217,  218 
undermining,  213 
zones  of,  214 
Carious  teeth,  extraction  of,  294 
Cartilaginous   growths   of    mouth, 

139 
Caruncle,  salivary,  39 
Caseation  of  pulp,  272 
Cast  of  mouth  for  artificial  teeth, 
324-326 
plaster-of-Paris,  325 
Stent's  composition  for,  325 
Catarrhal  stomatitis,  113 
after-treatment,  115 
symptoms,  114 
treatment,  114 
Cavities,  drving  of,  before  filling, 
229 
pneumatic,    of     face,    corrosion 
anatomy  of,  54 
technic  for,  54 
preparation  of,  befoi-e  filling,  231 
sterilizing  of,  before  filling,  236 
Cells,  ameloblastic,  87 
pulp,  79 


330 


INDEX 


Cement,  22 
and  amalgam  filling,  combination 

of,  224 
corpuscles,  77 
filling,  223,  255 
Cementum,  55,  77 
caries  of,  214 

chemical  constituents  of,  78,  79 
exostoses  of,  147 
hypertrophy  of,  147 
of  roots,  89 
thickening  of,  146 
Cheeks,  carcinoma  of,  144,  145 
Cheilognathochisma,  171 
Cheiloplasty,  172 
Chemical  action  of  bacteria,  104 
constituents  of  cementum,  78,  79 
of  dentin,  72 
of  enamel,  77 
Chisel,  enamel-,  233 
Chlorethyl  anesthesia,  313 
Chloroform  anesthesia,  321,  322 
Chlorphenol  in  destroying  pulp,278 
Chondroma  of  mouth,  139 

prognosis,  141 
Circular  ligament,  81,  89 
Clefts,    congenital,    in    region   of 
mouth,  169 
facial,  in  embryo,  171 
treatment  of;  172 
labial,  lateral,  in  embryo,  169, 171 
mesial,  of  lower  lip,  in  embryo, 
171 
of  upper  lip,  in  embryo,  170 
nasal,  in  embryo,  171 

lateral,  in  embryo,  169 
of  palate,  in  embryo,  171 

treatment,  172 
primitive  oral,  165 
Y-shaped,  in  embryo,  168 
Coated  tongue,  39 
Cocain  anesthesia,  315,  319 
Cocci,  112 
Cofferdam,  229 
Coffin  plate,  189 
Collum,  55 
Concretional  pulpitis,  269 

treatment  of,  270 
Concretions,  calcareous,  in  pulp,  81 
Condensing  gold,  hand  mallet  for, 
243 


Condyloid  process,  45 

fracture  of,  150 
Conidiospores,  118 
Connective  bridge,  84 
Constitutional  diseases  as  cause  of 

anomalies  of  teeth,  176 
Constructors,  dentin,  80 

enamel,  87 
Contracted  jaw,  185 

treatment  of,  189 
Convulsions,  94 

treatment  of,  94 
Copper-amalgam  filling,  222 
Corona,  55 
Coronoid  process,  45 
fracture  of,  150 
Corpuscles,  cement,  77 
Corrosion   anatomy   of  pneumatic 
cavities  of  face,  54 
of  teeth,  51 
of  pneumatic   cavities   of    face, 

technic  for,  54 
of  teeth,  technic  for,  51 
Cortical    substance    of   Walkhoff, 

74 
Cranial  nerve,  fifth,  49 
Creosote  anesthesia,  318 
Crescent-formed  defects  upon  inci- 
sors, 194 
Crowns,  55 

peiTuanent,    location    of,   before 
absorption  of  deciduous  roots, 
101 
Crystal  gold  filling,  221 
Cuspids,  24,  57 

deciduous,  time  of  eruption,  90, 

91 
lower,  58 

exti-action  of,  303 
permanent,  calcification  of,  99 

eruption  of,  100,  101 
upper,  57 

extraction  of,  301 
Cutting  surface  of  tooth,  55 
Cysts,  dermoid,  of  mouth,  131 
dilatation,  of  mouth,  131 
follicular,  of  mouth,  136 

treatment  of,  136 
of  mouth,  130,136 
periodontia!,  131 
periosteal,  of  mouth,131 


INDEX 


331 


Cysts,  retention,  of  mouth,  130 
root-,  131 

tooth,  follicular,  131 
periosteal,  131 
contents  of,  135 
treatment  of,  135 

Dall's  enamel  rods,  256 
Dam,  rubber,  229 

method  of  applying,  229 
punch  for,  229 
Deciduous  teeth,  64 
calcification  of,  89 
eruption  of,  90 
extraction  of,  309 
germs  of,  83 
premature  loss  of,  175 
resorption  of,  94 
Decubital  ulcei-s,  117 
treatment  of,  117 
Defects,   acquired,   of  hard   tooth 
substances,  195 
congenital,   of   hard   tooth   sub- 
stances, 192 
crescent-formed,  upon     incisors, 

194 
of  buccal  sui-face  of  teeth,  201 
efface,  163 

of  labial  surface  of  teeth,  201 
of  masticating  surface  of  teeth, 

201 
of  teeth,  filing  of,  218 
nitrate  of  silver  in,  219 
treatment  of,  217 
wedge-shaped,  197 
etiology  of,  199 
prevention  of,  200 
silver  nitrate  in,  200,  219 
treatment  of,  200 
Dental  rami,  48 
tissues,  hard,  69 

hard,  growths  of,  146 
soft,  69 
Denticola,  205 
Dentin,  22,  69 
anesthesia,  317 
caries  of,  212 

microscoj)ic  detection  of,  213 
chemical  constituents  of,  72 
constructoi"s,  80 
formation  of,  85 


Dentin,  germ,  85 

ground  substance  of,  70 

matrix  of,  70 

secondary,  259 
Dentinal  tubules,  70 

subdivision  of,  70 
Dentinogene  substauce,  86 
Dentistry,  history  of,  17 
Dentoidin,  199 
Denudations,  197 
Deposits,  190 

black,  191 

brown,  191 

green,  191 

white,  191 
Dermoid  cysts  of  mouth,  131 
Development  of  root,  88 

of  teeth,  82 
Diastatic  bacterial  ferment,  105 
Diazones  on  enamel,  76 
Dilatation  cysts  of  mouth,  131 
Diphtheria,  bacillus,  112 

method  of  staining,  112 
Diphyodont  teeth,  26 
Diplococcus  pneumoniffi,  111 
diseases  caused  by,  112 
method  of  staining.  111 
Disintegration,  106 
Dislocation    of    inferior    maxilla, 
45, 154 
causes,  154 
treatment,  1 55 
Distal  surface  of  tooth,  55 
Drving  of  cavities  before  filling, 

229 
Duct  of  Bartholin,  39 

of  Rivinus,  39 

of  Stenson,  32 

of  Wharton,  39 

Ear  in  embryo,  1 65 
Edema,  extraction  in,  296 
Elevator,  Langenbeck's,  307 
Elliott's  separator,  227 
P^mbrvology  of  head,  164 
Empyema,  extraction  in,  296 
of  antrum  of  Highmore,  155 

after-treatment,  162 

dental  causes,  156 

development  of,  156 

etiology,  156 


S32 


Index 


Empyema,  of  antrum  of  Highmore, 
hydrops  and,  155 
symptoms,  158 
treatment,  159 
Enamel,  21,  55,  73 

band,  82 

caries  of,  microscopic  detection 
of,  212 
objective  symptoms,  211 
pigmentation  in,  211 

chemical  constituents  of,  77 

constructors,  87 

covering,  partial  absence  of,  193 

cuticle,  73 

diazones  on,  76 

filling,  221 

germ,  87 

hyperplasia,  192 

hypoplasia,  99 

membrane,  73 

odontoma  adamantinum,  147 

organ,  82,  87 

parazones  on,  76 

prisms,  74 

rods.  Ball's,  256 

striations  on,  75 

walls,  overhanging,  removal  of, 
before  filling,  233 

zones  on,  76 
Enamel-chisel,  233 
Endosteal  fibroma  of  mouth,  139 
Engine,  burs  for,  235 
Enzymes,  105 
Epithelial  layer,  outer,  87 

nests,  82 
Epithelium,  88 

of  oral  cavity,  69 
Erosions,  192,  197 
Eruption  of  deciduous  teeth,  90 

of  permanent  teeth,  99 

of    teeth,    disturbances     accom- 
panying, 91 
mechanism  concerned  in,  89 
Ether  anesthesia,  321,  322 
Ethyl  broraid  anesthesia,  320 

•  chlorid  anesthesia,  313 
Ethylidene  lactic  acid,  107 
Excavator,  spoon-,  234 
Exostoses  of  cementum,  147 

of  mouth,  140 
Extraction,  293 


Extraction,  accidents  in,  309 

bruising    and    tearing    of     sur- 
rounding soft  parts  in,  311 
complications  during  and  after, 

309 
contraindications  to,  296 
fractures  of  lower  jaw  in,  310 

of  tooth  in,  310 

of  upper  jaw  in,  310 
hemophilia  in  296 
hemorrhage  after,  312 
in  diseases  of  jaw-bone,  294 
in  edema,  296 
in  empyema,  296 
in  maxillary  abscess,  296 
in  neuralgia,  294 
in  pregnancy,  296 
indications  for,  293 
infectious  processes  after,  311 
of  carious  teeth,  294 
of  deciduous  teeth,  309 
of  loose  teeth,  293 
of  lower  bicuspids,  305 

cuspids,  303 

incisors,  303 

molars,  305 

teeth,  301 
of  protruding  portions  of  roots, 

324 
of  reactionless  roots,  323 
of  roots,  306 
of  upper  bicuspids,  303 

cuspids,  301 

incisor's,  301 

molai-s,  303 

teeth,  299 
of  wisdom  teeth,  304,  306 
technic  of,  298 
wound  pains  after,  311 
Eye  in  embryo,  164 

Face,  defects  of,  acquired,  163 
diagnosis  of,  163 
treatment  of,  163 
congenital,  164 
luetic,  treatment  of,  163 
pneumatic  cavities  of,  corrosion 
anatomy  of,  54 
technic  for,  54 
Facial  clefts  in  embryo,  171 
treatment  of,  172 


INDEX 


333 


Facial  fissure,  oblique,  in  embryo, 
170 
transverse,  in  embryo,  170 
Fatty  degeneration  of  pulp,  272 
Fauces,  isthmus  of,  34 
Faucial  arches  in  embryo,  165 
Ferments,  albuminoid    dissolving, 
105 
bacterial,  105 
action  of,  105 
diastatic,  105 
proteolytic,  105 
Fibei-s,  Tomes',  71,  85 
Fibroma  of  mouth,  137 
deep  seated,  137 
endosteal,  139 
hard,  treatment,  139 
seat  of,  139 
soft,  treatment  of,  139 
superficial,  137 
symptoms  of,  138 
Fifth  cranial  nerve,  49 
Filing  in  defects  of  teeth,  218 
Filling,  220 

amalgam,  222,  252 
and  cement,  224 
cement,  223,  255 

and  amalgam,  224 
copper-amalgam,  222 
crystal  gold,  221 
drying  of  cavities  before,  229 
enamel,  224 

examination  of  teeth  before,  225 
fusible  glass  and  porcelain,  256 
gold,  221 
and  tin,  221 
cylinders,  221 
finishing  of,  250 
guttapercha,  225,  258 
for  root-canals,  279 
indestructibility  of,  220 
materials,  220 
plastic,  222 
matrices  in,  238 

metallic  pins,  for  root-canals,  279 
porcelain,  224,  255 
preparation  of    cavities    before, 

231 
removal  of  overhanging  enamel 

walls  before,  233 
root-canals,  guttapercha  for,  279 


Filling  root-canals,  material  for,  279 
metallic  pins  for,  279 
separating  molai-s  before,  227 

teeth  before,  226 
sterilizing  cavities  before,  236 
technic  of,  225 
tin  and  gold,  221 
with  cohesive  gold,  242 

anchorage  points  in,  245 
under-cuts  in,  245 
with  non-cohesive  gold,  240 
zinc  phosphate,  223 
Fissure,  facial,  oblique,  in  embryo, 
170 
transvei-se,  in  embrvo,  170 
Fistula  of  gum,  289 
Fluorescin,  106 
Follicular  cysts  of  mouth,  136 
treatment  of,  136 
tooth  cysts,  131__ 
Foramen,  apical,  79 
incisivura,  43 

in  embiyo,  168 
infraorbital,  42 
pterygopalatine,  37 
Forceps,  bayonet-shaped,  307 
for  left  upper  molars,  304 
for  lower  molars,  305,  306 
for  right  upper  molars,  304 
for  upper  bicuspids  and  certain 
roots  of  upper  jaw,  302 
incisor  and  cuspid  teeth,  301 
Eauhe's,  306 
Fornix,  Merkel's,  31 
Fossa,  canine,  41 

incisiva,  41 
Fractures  in  lower  jaw  in  extrac- 
tion, 310 
in  upper  jaw  in  extraction,  310 
of  alveolar  processes,  152 
of  ascending  ramus  of  jaw,  150 
of  condyloid  processes,  150 
of  coronoid  process,  150 
of  lower  jaw,  148 

after-treatment,  152 
method  of  applying  splints 

in,  151 
treatment,  150 
of  tooth  in  extraction,  310 
of  upper  jaw,  152 
Fi-senum,  32 


334 


INDEX 


Fragments,  tooth,  88 
Frankel's  diplococcus  pneumoniae, 
111 
diseases  caused  by,  112 
method  of  staining.  111 
Frontal  process,  41 

in  embiyo,  164,  166 
Fungi,  mould,  in  mouth,  113 
thrush,  examination  of,  113 
Furrow,  mentolabial,  29 

Gangrene  of  pulp,  268 
treatment,  269,  279 
Gas,  laughing,  anesthesia  with,  319 

pit,  108 
Gases  from  bacteria,  107,  108 
Germs,  dentin-,  85 

of  enamel,  87 

of  deciduous  teeth,  83 

of  molars,  84 

of  permanent  incisors,  84 
Giant-celled  sarcoma  of  mouth,  141 
Gingival  perforating  branches   of 

interalveolar  rami,  48 
Gland,  parotid,  32 

inflammation  of,  33,  126 
Glandula  incisiva,  39 
Globular  processes  in  embrvo,  166, 

168 
Glomeruli,  vascular,  82 
Gold  and  tin  filling,   combination 
of,  221 

cohesive,  filling  with,  242 
anchorage  points  in,  245 
under-cuts  in,  245 

condensing  of,  hand  mallet  for, 
243 
pluggers  for,  243 

crystal,  filling  with,  221 

cylinders  filling,  221 

filling,  221 

finishing  of,  250 

hammer,  Kirlsy-Eauhe's,  244 

non-cohesive,  filling  with,  240 
Granular  layer  of  Tomes,  70 
Granulation   tissue,    formation    of, 

near  diseased  molar  root,  158 
Granules,  calcium,  of  pulp,  273 
Granuloma,  132 
Granulomatous     periodontitis, 

chronic,  287 


Granulomatous    periodontitis, 

hypertrophic,  267 
Greater  palatine  artery,  37 

nerve,  37 
Green  deposits,  191 
Grinders,  59 

Grinding  surface  of  tooth,  55 
Groove,  nasal,  in  embryo,  166, 168 

oculonasal,  in  embryo,  168,  170 

of  mouth  in  embryo,  167 

pterygopalatine,  42 

true,  193 
Gums,  carcinoma  of,  144,  146 

fistula  of,  289 
Guttapercha  filling,  225,  258 
for  root-canals,  279 

Hair  and  teeth,  ]-elations,  176 
Hammer,  Kirby-Eauhe's,  244 
Haplodont  teeth,  28 
Hard  fibroma  of  mouth,  treatment, 
139 

palate,  arteries  of,  37 
Hare-lip,  cheiloplasty  for,  172 

in  embryo,  169 

treatment  of,  172 
Head,  embryology  of,  164 
Hemophilia,  estjaction  in,  296 
Hemorrhage  after  extraction,  312 
Herbst's   method    of  condensation 

of  gold  by  rotation,  249 
Heterotopia,  180 

par  g^nese,  181 
Hiatus,  maxillary,  41 
Highmore,  antrum  of,  41 

empyema   of,    155.     See    also 
Empyema  of  anlrum  of  High- 
more. 
Histology,  67 
History  of  dentistry,  17 
Honey-comb  teeth,  193 
Humped  teeth,  24 
Hydrogen,  sulphuretted,  108 
Hyperemia  of  pulp,  261 
Hyperostoses  of  mouth,  140 
Hyperplasia,  enamel,  192 
Hypertrophy  of  cementum,  147 

of  roots,  146 
Hypoplasia,  192 

enamel,  99 

treatment,  194 


INDEX 


335 


Hypsolodont  teeth,  22 

Idiopathic  pulpitis,  269 

treatment  of,  270 
Incipient  caries,  201 
Incisal  surface  of  tooth,  55 
Incisive  fossa,  41 
Incisoi-s,  57 

crescent-formed    defects     ujDon, 

194 
deciduous,  time  of  eruption,  90, 

91 
lower,  57 

extraction  of,  303 
permanent,  calcification  of,  99 
eruption  of,  100,  101 
germs  for,  84 
upper,  57 

extraction  of,  301 
variations  in  form  of,  23 
Indestructibility  of  filling,  220 
India-rubber  splint,  151 
Indolent  pulps,  275 
Infantile  odontalgia,  92 
treatment  of,  92 
odontitis,  93 
treatment  of,  93 
Infectious  processes   after  extrac- 
tion, 311 
Inferior    maxilla,   44.      See    also 

Maxilla^  inferior. 
Influenza  bacilli,  111 

method  of  staining,  111 
Infraorbital  artery,  49 
foramen,  42 
nerve,  49 
niedii  of,  50 

posterior  branches  of,  50 
sulcus,  42 
InfusorijB  in  cause  of  caries,  205 
Insufficient  number  of  teeth,  184 

treatment,  188 
Interalvoolar  rami,  48 

alveolar  perforating  bi-aiiches 

of,  48 
gingival  j)erforating  branches 
of,  48 
Interglobular  spaces,  72 
Internal  maxillai-y  artery,  48 
pterygopalatine  plexus,  49 
Interradicular  abscess,  286 


Isodont  type  of  tooth,  22 
Isthmus  of  fauces,  34 

Jaw,  anomalies  of,  174 

ascending  ramus  of,  fracture  of, 

150 
contracted,  185 

treatment  of,  189 
lower,  44.     See  also  Maxilla,  in- 
ferior. 
upper,    41.      See  also    3Iaxilla, 

superior. 
V-shaped,  185 
treatment  of,  189 
Jaw-bone,    diseases   of,   extraction 

of  teeth  in,  294 
Joints  of  inferior  maxilla,  45 
Juga  alveolarls,  41 

Kataphorests,  anesthesia  by,  318 
Kirby-Eauhe's       automatic     gold 

hammer,  244 
Kohinoor  matrix,  239 

Labial  cleft,  lateral,  in  embryo, 
171 
sui-face  of  teeth,  55 
defects  of,  201 
Labium  leporium  in  embryo,  171 
Lactic  acid,  107 

ethylidene,  107 
Lacunse,  193 

bowl-shaped,  193 
resorption,  97 
Lamina  lacrymalis,  42 
Langenbeck's   periosteal    elevator, 

307 
Laughing  gas,  anesthesia  by,  319 
Layer,  epithelial,  outer,  87 
Leptothrix  buccalis,  112 
in  cause  of  caries,  207 
method  of  staining,  112 
Lenkeinia,     ulcerative     stomatitis 

after,  115 
Lisjament,  alveolar,  81 

circular,  81,  89 
Lime  concretions  of  pulp,  273 
Lines  of  Schreger,  75,  76 
Lingual  surface  of  tooth,  55 
Lip,  carcinoma  of,  144 
prognosis,  144 


336 


INDEX 


Lip,  carcinoma  of,  treatment,  145 
lateral  cleft  of,  in  embryo,  169 
lower,  mesial  cleft  of,  in  embryo, 

171 
scirrhous  carcinoma  of,  144 
upper,  mesial  cleft  of,  in  embryo, 
170 
Lipoma  of  mouth,  141 

treatment,  141 
Localization  of  teeth,  237 
Loffler's  bacillus,  112 

method  of  staining,  112 
Loose  teeth,  exti-action  of,  293 
Lophodont  teeth,  24,  26 
Lower  jaw,  44.     See  also  Maxilla, 

inferior. 
Lymphatics  of  pulp,  80 

Mallet,    hand,     for    condensing 

gold,  243 
Malocclusion  of  teeth,  185 
Mammalian  teeth,  anatomy  of,  21 
development  of,  from  original 
state,  28 
Mandibula,  44 
Mandibular  canal,  45 

vein,  49 
Mark,  57 

Masses  epith^liaux,  82, 133,  134 
Masticating  surface  of  teeth,  55 

defects  of,  201 
Matrices,  238 
Kohinoor,  239 
Millei-'s,  239 
Maxilla,  41 
inferior,  44 

dislocation  of,  45,  154 
causes,  154 
treatment,  155 
fractures  in,  in  extraction,  310 
fractures  of,  148 
after-treatment,  152 
method  of  applying  splints 

in,  151 
treatment,  150 
in  embryo,  165 
joints  of,  45 

prognathism  of,  174,  185 
treatment,  189 
superior,  38 
alveolar  process  of,  49 


Maxilla,  superior,  fractures  in,  in 
extraction,  310 
fi-actures  of,  152 
prognathism  of,  174 
Maxillary   abscess,    extraction  in, 
296 
artery,  internal,  48 
hiatus,  41 
process,    superior,    in     embryo, 

165,  168 
sinus,  41 
tuberosity,  42 
Medii  of  infraorbital  nerve,  50 
Mentolabial  furrow,  29 
Mercaptan,  putrid,  108 
Mercurial  stomatitis,  115 
Merkel's  fornix,  31 
Mesial  cleft  of  lower  lip  in  embryo, 
171 
of  upper  lip  in  embryo,  170 
surface  of  tooth,  55 
Metabolic     products    of    bacteria, 

105 
Metallic  pins  for  filling  root-canals, 

279 
Midbrain  in  embryo,  164 
Milk  teeth,  27 
Millei-'s  matrix,  239 
Molars,  24,  59 

deciduous,    time    of     eruption, 

90,91 
germs  for,  84 
lower,  62 

extraction  of,  305 
permanent,  calcification  of,  99 

eruption  of,  100,  101 
sepai-ating,  before  filling,  227 
upper,  59 

extraction  of,  303 
Monilia  Candida,  113 
Mordex  apertus  carabelli,  185 
Morphology  of  schizomycetes,  103 
Mould  fungi  in  mouth,  113 
Mouth,  adenocarcinoma  of,  143 
anatomy  of,  33 
external,  29 
bacteriology  of,  102 
benign  growths  of,  130 
cancroid  of,  143 
carcinoma  of,  142 
cartilaginous  growths  of,  139 


INDEX 


337 


Mouth,  cast  of,  for  artificial  teeth, 

324-326 
chondroma  of,  139 

prognosis,  141 
congenital  clefts  in  region  of,  1^9 
cysts  of,  130 

classification,  130 
dermoid  cysts  of,  131 
dilatation  cysts  of,  131 
diseases  of,  113 
embryology  of,  164 
endosteal  fibroma  of,  139 
epithelium  of,  69 
exostoses  of,  140 
external  anatomy  of,  29 
fibroma  of,  137 

deep  seated,  137 

endosteal,  139 

hard,  treatment  of,  139 

seat  of,  139 

soft,  treatment  of,  139 

superficial,  137 

symptoms,  138 
floor  of,  37 

anatomy  of,  34 

arteries  of,  40 

carcinoma  of,  144,  145 

nerves  of,  40 
follicular  cysts  of,  136 
treatment  of,  136 
giant-celled  sarcoma  of,  141 
grooves  of,  in  embryo,  167 
hard   fibroma  of,  treatment,  139 
hyperostoses  of,  140 
lipoma  of,  141 

treatment,  141 
malignant  growths  of,  141 
mould  fungi  in,  113 
mucous  membrane  of,  67 
cellular  elements,  68 
papilla>  of,  35 
nerve  supply  of,  37 
osteoma  durum  of,  139 

prognosis,  141 

spongiosum,  130 
osteophytes  of,  140 
periosteal  cysts  of,  131 
preparation  of,  for  artificial  teeth, 

323 
retention  cysts  of,  130 
roof  of,  anatomy  of,  34 

•22 


Mouth,  roof  of,  in  embryo,  168 
round-celled  sarcoma  of,  141 
sarcoma  of,  141 
diagnosis,  142 
diflerential  diagnosis,  142 
treatment,  142 
soft  fibroma  of,  treatment,  139 
spindle-celled  sarcoma  of,  141 
submucous  membrane  of,  67 
syphilis  of,  126.    See  also  Syphilis 

of  mouth. 
tuberculosis  of,  129 
tumors  of,  130 
Mucosa  oris,  67 

Mucous  membrane  of  mouth,  67 
cellular  elements,  68 
papillte  of,  35 
Mumps,  126 
Muscle,  canine,  41 

mylohyoid,  34 
Mycelii,  113 
Mycotic  stomatitis,  118 

treatment  of,  119 
Mylohyoid  muscle,  34 

Nasal  clefts  in  embryo,  169,  171 

groove  in  embryo,  166,  168 

processes  in  embryo,  165, 166, 168 
middle,  in  embryo,  165 
lateral,  in  embryo,  165 

septum  in  embryo,  166 
Nasopalatine  nerve,  37 
Neck,  54 
Necrosis  eboris,  201 

of  apex  of  root-membrane,  287 

of  bony  plate,  157 

of  root-membrane,  287 
Nerves,  alveolar  anterior,  50 

cranial,  fifth,  49 

infraorbital,  49 
medii  of,  50 
posterior  branches  of,  50 

nasopalatine,  37 

of  floor  of  mouth,  40 

of  pulp,  80 

of  teeth,  48 

palatine,  greater,  37 

supplying  oral  cavity,  37 

trigeminal,  49 
Ncrvocidin    in     destroying    pulp, 

277 


S38 


INDEX 


Nests,  epithelial,  82 
Neumann's  sheath,  71,  85 
Neuralgia,  extraction  in,  294 
Nippers,  323 
Nitrate    of    silver  in   defects    of 

teeth,  219 
Nitrous  oxid  anesthesia,  319 
Noma,  121 

prognosis,  121 

treatment,  121 
Nose  in  embryo,  164 

saddle-,  syphilitic,  129 

Obturator    for  cleft    of   palate, 

172 
Oculonasal  groove  in  embryo,  168, 

170  ^ 

Odontalgia,  infantile,  92 

treatment  of,  92 
Odontitis,  infantile,  93 

treatment  of,  93 
Odontoblasts,  80,  85 
Odontoma,  147 

external,  147 

internal,  147 
Odontoporosis,  194 
Oi'dium  albicans,  113 
Olfactory  organ  in  embryo,  164 
Opisthognathism,  treatment  of,  189 
Oral  cavity.     See  Mouth. 

cleft,  primitive,  165 

vestibule,  anatomy  of,  30 
Orbital  surface,  42 
Organ,  enamel,  82,  87  "  - 

Orthognathism,  176,  184 
Osteoclasts,  97,  98 
Osteoma  durum  of  mouth,  139 

of  mouth,  139 
prognosis,  141 

spongiosum  of  mouth,  139 
Osteo-odontoma,  147 
Osteophytes  of  mouth,  140 
Ostium  maxillare,  41 
Ozoena  syphilitica,  129 

Palate,  carcinoma  of,  144,  145 

cleft  of,  in  embryo,  171 
treatment,  172 

hard,  arteries  of,  37 

papilla  of,  35 
Palatine  arch,  34 


Palatine,  artery,  greater,  37 
nerve,  greater,  37 
process,  41,  43 
surface  of  tooth,  55 
Palatum  fissum  in  embryo,  171 
Papillse  of  oral  mucous  membrane, 
35 
of  palate,  35 
Paramonochlorphenol     anesthesia, 

318 
Parazones  on  enamel,  76 
Parenchymatous  pulpitis,  chronic, 
265 
treatment  of,  266 
Parotid  gland,  32 
Parotitis,  33, 126 

primary  idiopathic,  126 
prognosis,  126 
treatment,  126 
Parulis,  289 
Peg-shaped  teeth,  182 
Penetrating  caiies,  213 
Pepsin,  105 
Peptonizing   activity   of   bacteria, 

199 
Perichymates,  73 
Periodontia!  cvst,  131 
Periodontitis,  283 
acute,  285 
apical,  285 
circumscribed,  285 
diffuse,  285  ^ 
marginal,  285 
purulent,  286 
unilateral,  285 
chronic,  287 
apical,  287 
diffiise,  287 
granulomatous,  287 
pm-ulent,  287 
classification  of,  284 
course  of,  288 
toxic,  286 
treatment  of,  290 
Periodontum,  81 
Periosteal  cysts  of  mouth,  131 
tooth  cysts,  131 

contents  of,  135 
treatment  of,  135 
Periosteum,  81 
alveolar,  56 


INDEX 


339 


Permanent    crowns,    location     of, 
before  absorption  of  deciduous 
roots,  lUl 
incisoi's,  germs  for,  84 
teeth,  56 

calcification  of,  99 
eruption  of,  99 
loss  of,  175 
Pharynx,    adenoid   growths  of,  ef- 
fect on  teeth,  174 
Pliiltrum  in  embryo,  167 
Physiology,  82 

Pigments,  black,  from  bacteria,  167 
brown,  from  bacteria,  106 
from  bacteria,  106 
Pit  gas,  108 
Plaques  opalines,  127 
Plaster-of-Paris  cast,  325 
Plastic  filling  material,  222 
Plate,  bonv,  necrosis  of,  157 

coffin,  189 
Plexus,   pterygopalatine,    internal, 

49 
Plicse  palatinae,  35 
Pluggei-s  for  condensing  gold,  242 
Pneumatic  cavities  of  face,  corro- 
sion anatomy  of,  54 
technic  for,  54 
Porcelain  and  fusible  glass  filling, 
256 
filling,  224,  255 
Pravaz  syringe,  317 
Pregnancy,  extraction  in,  296 
Preiswerk's   method    of    inserting 

gold  filling,  247 
Premolars,  58 
Primitive  oral  cleft,  165 
Prisms,  enamel,  74 
Process,  alveolar,  41 
absorption  t)f,  37 
fractures  of,  152 
lower  boi-der  of,  43 
of  upper  iaw,  49 
condyloid,  *b 

fractures  of,  150 
coronoid,  45 
frontal,  41 

in  embryo,  164,  166 
gloinilar,  in  embryo,  166,  168 
maxillary,  superior,  in  embryo, 
165,168 


Process,  nasal,  in  embryo,  166,  168 
palatine,  41,  43 
Tomes',  87 
Prodigiosin,  106 
Prognathism,  177,  184 

of  inferior  maxilla,  174,  185 

treatment  of,  189 
of  superior  maxilla,  174 
Proteolytic  ferment,  105 
Protococcus  dentalis   in  cause   of 

caries,  205 
Pterygopalatine  foramen,  37 
groove,  42 
plexus,  internal,  49 
Pulp,  79,  85 
abscess  of,  272 
amputation  of,  281 
application  of  caj)  to,  276 
ai'senic  in  desti'oying,  277 
blood-vessels  of,  80 
calcareous  concretions  in,  81 
calcium  granules  of,  273 
caseation  of,  272 
cells,  79 

chlorphenol  in  destroying,  278 
degenerative  processes  of,  271 
destruction    and   extirpation   of, 

277 
diseases  of,  259 
anatomic  remarks  concerning, 

271 
diagnosis,  275 

pathologic    remarks    concern- 
ing, 271 
treatment,  276 
extirpation   and   destruction  of, 

277 
fatty  degeneration  of,  272 
gangrene  of,  268 

treatment,  269,  279 
hyperemia  of,  261 
indolent,  275 
lime  concretions  of,  273 
lymphatics  of,  80 
nerves  of,  80 

nervocidin  in  destroying,  277 
regressive  disturbances  in  nutri- 
tion of,  271 
removal  of,  in  root-canals,  278 
reticular  atrophy  of,  273 
sclerosis  of,  274 ' 


340 


INDEX 


Pulp,  senile,  274 

septic  inflammation  of,  262 
tannic  acid  in  destroying,  278 
Pulpitis,  259 

acute  partial,  263,  264 
purulent,  265 
superficial,  262 

treatment  of,  263 
total,  263,  264 
ascending,  259 

chronic  hypertrophic  granulom- 
atous, 267 
sarcomatous,  267 
parenchymatous,  265 

treatment  of,  266 
total  purulent,  265 
concretional,  269 

treatment  of,  270 
diagnosis  of,  275 
idiopathic,  269 

treatment  of,  270 
traumatic,  263 
Punch  for  rubber  dam,  229 
Purulent  periodontitis,  chronic,  287 
pulpitis,  chronic  total,  265 
partial,  265 
Putrefaction,  107 

products  of,  107 
Putrefactive  bacteria,  107 
Putrid  mercaptan,  108 
Pj'ocj^anin,  106 
Pyorrhea,  alveolar,  122 

avoiding  recurrence,  125 
etiology  of,  122 
patho-anatomic  changes  in,  123 
symptoms  of,  123 
treatment  of,  124 
Pyriform  aperture,  42 

Eadix,  55 

Kami,  ascending,  of  jaw,  fracture 
of,  150 
dental,  48 
interalveolar,  48 

alveolar  perfoi-ating  branches 

.  ^^'.^^ 
gingival  perforating  bmnches 

of,  48 

Kanine  artery,  40 

Raphe,  35 

Eauhe's  forceps,  306 


Reactionless   roots,  extraction   of, 

323 
Keimplantation,  292 
Eeplantation,  292 
Eesorption  lacuuEe,  97 

of  deciduous  teeth,  94 
Eetention  cysts  of  mouth,  130 
Eetzius  striae,  75 
Eivinus'  ducts,  39 
Eoot,  55 

cementum  of,  89 

development  of,  88 

extraction  of,  306 

membrane,  81 

protruding   portions  of,    extrac- 
tion of,  324 

reactionless,  extraction  of,  323 
Root-canals,  atresia  of,  280 

filling  of,  guttapercha  for,  279 
metallic  pins  for,  279 

material  for  filling,  279 

removal  of  pulp  in,  278 
Eoot-cyst,  131 
Eoot-membrane,  81 

apex  of,  necrosis  of,  287 

apical  abscess  of,  286 

diseases  of,  283.     See  also  Perio- 
dontitis. 

necrosis  of,  287 
Eound-celled    sarcoma   of  mouth, 

141 
Eubber  dam,  229 

method  of  applying,  229 
punch  for,  229 
Eump,  169 

Sac,  tooth,  85 

Saccharomyces  albicans,  113 

Saddle-nose,  syphilitic,  129 

Salivary  caruncle,  39 

Salt  solution  for  anesthesia,  314 

Sarcinse,  112 

Sarcoma,  giant-celled,  of  mouth,  141 
of  mouth,  141 
diagnosis,  142 
differential  diagnosis,  142 
treatment,  142 
round-celled,  of  mouth,  141 
spindle-celled,  of  mouth,  141 

Sarcomatous  pulpitis,  chronic  hy- 
pertrophic, 267 


INDEX 


341 


Schizomycetes,     moi-phology    and 

biology  of,  103 
Schleich's  solution,  315 
Schregei-'s  lines,  75,  76 
Sclerosis  of  pulp,  274 
Secodont  teeth,  24 
Selenodont  teeth,  24,  26 
Senile  pulp,  274 

Separating   molars    before   filling, 
227 

teeth  before  filling,  226 
Separator,  Elliott's,  227 
Septic  infiammation  of  pulp,  262 
Septum,  nasal,  in  embryo,  166 
Shape  of  teeth,  56 
Sheath,  Neumann's,  71,  85 
Silver  nitrate  in  caries,  219 

in  wedge-shaped  defects,  200, 
219 
Sinus,  maxillary,  41 
Six-year  molar,  59 
Soft  fibroma  of  mouth,  treatment, 

139 
Spaces,  interglobular,  72 
Spatula,  252 

Specific  alveolar  caries,  122 
Spindle-celled  sarcoma   of  mouth, 

141 
Splint,  India-rubber,  151 

manner  of  applying  in  fractures 
of  lower  jaw,  151 

tooth,  151 

wire,  151 
Spoon-excavator,  234 
Stain,  Ziehl-Neelsen,  for   tubercle 

bacilli,  111 
Staining  brcilli  of  influenza,  111 

diplococcus  pneumonije.  111 

leptothrix  buccalis,  112 

methods,  110 
Staphyloi-ihaphy,  1 72 
Stenson's  duct,  32 
Stent's  composition  for  cast,  325 
Sterilizing   cavities   before   filling, 

236 
Stomacace,  115 
Stomatitis,  aphthous,  117 
treatment  of,  118 

catarrhal,  113 
after-treatment,  115 
symptoms,  114 


Stomatitis,  catan-hal,  treatment,  114 
mercurial,  115 
mycotic,  118 
prognosis,  119 

treatment,  119 
ulcerative,  115 

after  leukemia,  115 
in  children,  116 
in  typhoid  fever,  115 
scorbutic  form,  115 
treatment,  116 
ulceroso  organisms  in,  112 
Stomatomycosis  oidica,  118 
Stratum  intermedium,  87 
Streptococci  in  caries,  207 
Striae  of  Eetzius,  75 
Striations  on  enamel,  75 
Submucous  membrane  of  mouth,  67 
Subperiosteal  abscess,  double-sided, 

289 
Sucking  thumb,  effect  on  teeth,  176 
Sugar,  convereion  of,  into  acid,  by 

bacteria,  106,  107 
Sulcus,  infraorbital,  42 

nasolabial,  29 
Sulphuretted  hydrogen,  108 
Superficies  orbitalis,  42 
Superior  maxilla,  38,  41.     See  also 
Maxilln,  superior. 
posterior  alveolar  arteries,  49 
Supernumerary  teeth,  182 

treatment  of,  188 
Syphilis,  defects  of  face  from,  treat- 
ment, 163 
of  mouth,  126 

difierential  diagnosis,  128 
primary  affection,  126 
prognosis  of,  127 
secondary  symptoms,  127 
subjective  symptoms,  127 
symptoms  of,  127, 128 
tertiary  SAinptoms,  128 
transmission  of,  126 
treatment,  129 
Syphilitic  saddle-nose,  129 
Syringe,  air,  for  drying  cavities,  235 
Pravaz,  317 
water,  251 

Tannic  acid  in  destroying  pulp, 
278 


342 


INDEX 


Tartar,  190  .  _ 

Technic  for  corrosion  of  pneumatic 
cavities  of  face,  54 
of  teeth,  51 
Teeth,  absence  of,  22 

anastomotic  canal  system  of,  53 
anatomy  of,  comparative,  21 
corrosion,  51 
special,  55 
and  hair,  relations,  176 
anisodontous,  22 
anomalies  of,  174 

constitutional  diseases  as  cause, 

176 
entire  row,  184 

treatment,  189 
form  of,  177 
insufficiency  of  space  as  cause, 

175 
position  of,  179 

treatment,  186 
ti-aumatism  as  cause,  176 
approximal  surface  of,  55 
articulations  of,  65 
artificial,  cast  of  mouth  for,  324- 
326 
preparation  of  mouth  for,  323 
biscuspid,  58 
blood-vessels  of,  48 
brachyodont,  22 
buccal  surface,  55 
defects  of,  201 
bunodont,  24 
canine,  57 

carious,  extraction  of,  294 
comparative  anatomy  of,  21 
corrosion  anatomy  of,  51 

technic  for,  51 
crown  of,  55 
cuspid,  24,  57 
cutting  surface,  55 
cysts  of,  follicular,  131 
periosteal,  131 
contents  of,  135 
treatment,  135 
deciduous,  64 

calcification  of,  89 
eruption  of,  90 
extraction  of,  309 
germs  of,  83 
premature  loss  of,  1 75 


Teeth,  deciduous,  resorption  of,  94 
defects  of,  filling  in,  218 

nitrate  of  silver  in,  219 

treatment  of,  217 
development  of,  82 
diphyodont,  26 
distal  surface  of,  55 
eruption  of,  disturbances  accom- 
panying, 91 

mechanism  concerned  in,  89 
examination  of,  for  tilling,  225 
fragments  of,  88 
grinders,  59 
grinding  surface  of,  55 
haplodont,  28 
histology  of,  67. 
honey-comb,  193 
humped,  24 
hypsolodont,  22 
incisal  surface  of,  55 
incisors,  57 

variations  in  form,  23 
insufficient  number  of,  176,  184 

treatment,  188 
isodont,  22 
labial  surface  of,  55 
defects  of,  201 
lingual  surface  of,  55 
localization  of,  237 
loose,  extraction  of,  293 
lophodont,  26 
malocclusion  of,  185 
mammalian,  anatomy  of,  21 

development  of,  from  original 
state,  28    - 
masticating  surface  of,  55 

defects  of,  201 
mesial  surface  of,  55 
milk,  27 
molar,  24,  59 
neck  of,  55 
nerves  of,  48 
palatine  surface  of,  55 
peg-shaped,  182 
permanent,  56 

calcification  of,  99 

eruption  of,  99 

loss  of,  175 
premolar,  58 
roots  of,  55 
sacs,  85 


INDEX 


343 


Teeth,  secodont,  24 

selenodont,  24,  26 

separating,  before  filling,  226 

shape  of,  56 

special  anatomy  of,  55 

splints  for,  151 

substances,   hard,    acquired    de- 
fects of,  195 
congenital  defects  of,  192 

supernumerary,  182 
treatment  of,  188 

temporary,  64 

torsion  of,  treatment,  188 

transposition  of,  181 

triconodont,  29 

tritubercular,  29 

veins  of,  49 
Temporary  teeth,  64 
Thermometer  of  Walkhoff,  275 
Thickening  of  cementum,  146 
Thrush,  113,  118 

fungus,  examination  of,  113 
Thumb,  sucking  of,  effects  on  teeth, 

176 
Tin  and  gold  filling,  combination 

of,  221 
Tomes'  fibers,  71,  85 

granular  layer,  70 

processes,  87 
Tongue,  anatomy  of,  39 

carcinoma  of,  144,  145 

coated,  39 
Tooth.     See  Teeth 
Tooth-band,  82 

aberration  of,  176 
Torsion  of  teeth,  treatment,  188 
Toxic  |)ci'iod(intilis,  286 
Transplantation,  181,292 
Traumatic  pulpitis,  263 
Traumatism  as  cause  of  anomalies 

in  teeth,  176 
Triconodont  teeth,  29 
Ti-igeminal  nerve,  49 
Tritubercular  teeth,  29 
Trypsin,  105 
Tubercle,  articular,  45 

bacilli,  110 

method  of  staining,  110 
Ziehl-Xeelsen  stain  for,  111 
Tubercvdosis  of  mouth,  129 
Tuberosity,  maxillary,  42 


Tubules,  dentinal,  70 
subdivision  of,  70 
Tumors  of  oral  cavity,  130 
Twelve-year  molar,  59 
Typhoid  fever,  ulcerative  stomatitis 
in,  115 

Ulcerative  stomatits,  115.     See 

also  Stomatitis,  vlcerative. 
Ulcers,  decubital,  117 
treatment  of,  117 
Undermining  caries,  213 
Undulations,  192 
Upper  jaw,  41.     See  also  Maxilla, 

superior. 
Uranocoloboma,  171 
Uranoplasty,  172 
Uvula,  37 

Vascular  glomeruli,  82 
Veins,  mandibular,  49 

of  teeth,  49 
Vestibule,  oral,  anatomy  of,  30 
V-shaped  jaw,  185 
treatment  of,  189 

"\VALKHOFF,corticalsubstanceof,74 

thermometer,  275 
Water  syringe,  251 
"VVedge-shaped  defects,  197 

etiology  of,  199 

prevention  of,  200 

silver  nitrate  in,  200,  219 

treatment  of,  200 
"Wharton's  duct,  39 
White  deposits,  191 
Wire  splint,  151 
AVisdom  teeth,  59 

extraction  of,  304,  306 
Wound  pains  after  extraction,  311 

Xanthix,  106 

Y-SHAPED  cleft  in  embryo,  168 

Ziehl-Neelsen  stain  for  tubercle 

bacilli,  111 
Zinc  chlorid  anesthesia,  318 

phosphate  filling,  223 
Zones  on  enamel,  76 
Zygoma,  41 


2  SAUNDERS'   MEDICAL   HAND-ATLASES 

saunders' 
Medical  Hand-Atlases 

¥N  planning  this  series  of  books  arrangements  were  made  with 
representative  pubHshers  in  the  chief  medical  centers  of  the 
world  for  the  publication  of  translations  of  the  atlases  in  thir- 
teen different  languages,  the  lithographic  plates  for  all  being 
made  in  Germany,  where  work  of  this  kind  has  been  brought  to 
the  greatest  perfection.  The  enormous  ex- 
pense of  making  the  plates  being  shared  by 
the  various  publishers,  the  cost  to  each  one 
was    reduced  approximately  to    one-tenth. 


Moderate 
Price 


Thus,  by  reason  of  their  universal  translation  and  reproduction, 
affording  international  distribution,  tne  publishers  have  been 
enabled  to  secure  for  these  atlases  the  best  artistic  and  profes= 
sional  talent,  to  produce  them  in  the  most  elegant  style,  and 
yet  to  offer  them  at  a  price  heretofore  unapproached  in  cheapness. 
One  of  the  most  valuable  features  of  these 
atlases  is  that-  they  offer  a  ready  and  satis= 
factory  substitute  for  clinical  observation. 
Such  observation,  of  course,  is  available  only 
to  the  residents  in  large  medical  centers ; 


Substitute 
for  Clinical 
Observation 


and  even  then  the  requisite  variety  is  seen  only  after  long  years 
of  routine  hospital  work.  To  those  unable  to  attend  important 
clinics  these  books  will  be  absolutely  indispensable,  as  presenting 
in  a  complete  and  convenient  form  the  most  accurate  reproduc- 
tions of  clinical  work,  interpreted  by  the  most  competent  of 
clinical  teachers. 


Adopted  by 
U.  S.  Army 


As  an  indication  of  the  great  practical  value 
of  the  atlases  and  of  the  immense  favor  with 
which  they  have  been  received,  it  should  be 
noted  that  the  Medical  Department  of  the  U.  S.  Army  has  adopted 
the  '  'Atlas  of  Operative  Surgery  ' '  as  its  standard,  and  has  ordered 
the  book  in  large  quantities  for  distribution  to  the  various  regi- 
ments and  army  posts. 


SAUNDERS'  MEDICAL  HAND-ATLASES  3 

Preiswerk  and  Warren's 
Dentistry 

Atlas  and  Epitome  of  Dentistry.  By  Prof.  Gustav 
Preiswerk,  of  Basil.  Edited,  with  additions,  by  George  W. 
Warren,  D.D.S.,  Professor  of  Operative  Dentistry  at  the  Penn- 
sylvania College  of  Dental  Surgery.  With  44  lithographic  plates 
in  colors,  152  text-cuts,  343  pages  of  text.     Cloth,  $3.50  net. 

JUST   READY 

Preiswerk's  atlas  will  be  fuund  invaluable  to  the  practicing  dentist,  for  the 
numerous  excellent  lithographs  make  very  easy  of  comprehension  those  pro- 
cedures that  would  be  but  imperfectly  understood  from  description  alone. 

The  Dental  Review 

"  Nowhere  in  dental  literature  have  we  ever  seen  illustrations  which  can  begin  to  com- 
pare with  these  exquisite  colored  plates." 

Hecker,  Trumpp,  and  Abt 
on  Children 


Atlas  and  Epitome  of  Diseases  of  Children.  By  Drs.  R. 
Hecker  and  J.  TruiMPP,  of  Munich.  Edited,  with  additions,  by 
Isaac  A.  Abt,  M.D.,  Assistant  Professor  of  Diseases  of  Children, 
Rush  Medical  College.  With  48  lithographic  plates  in  colors, 
147  text-cuts,  and  453  pages  of  text.      Cloth,  $5.00  net. 

JUST   READY 

It  is  a  recognized  fact  that  the  Germans  lead  the  world  in  the  treatment  of 
children's  diseases,  and  this  magnificent  atlas  fully  maintains  this|  reputation 
The  lithographic  plates  are  wonderfully  accurate,  and  the  accompanying  text 
is  particularly  full  on  treatment.  Dr.  Isaac  Abt,  the  editor,  has  greatly  im- 
proved the  work  by  the  addition  of  all  the  latest  methods  of  treatment  and 
diagnosis. 

Each  volume  conteuns  from  50  to  100  colored  plates 


SAUNDEJiS'    MEDICAL   HAND-ATLASES 

Zuckerkandl  and  DaCosta's 
Operative  Surgery 

Second  Edition,  Revised  and  Greatly  Enlarged 


Atlas  and  Epitome  of  Operative  Surgery.     By  Dr.  O. 

Zuckerkandl,  of  Vienna.  Edited,  with  additions,  by  J-  Chal- 
mers DaCosta,  M.  D.,  Professor  of  the  Principles  of  Surgery 
and  Chnical  Surgery,  Jefferson  Medica'  College,  Philadelphia. 
With  40  colored  plates,  278  text-cuts,  and  410  pages  of  text. 
Cloth,  $3-50  net. 

ADOPTED  BY  THE  U.  S.  ARMY 

In  this  new  edition  the  work  has  been  brought  precisely  down  to  date. 
The  revision  has  not  been  casual,  but  thorough  and  exhaustive,  the  entire 
text  having  been  subjected  to  a  careful  scrutiny,  and  many  improvements  and 
additions  made.  A  number  of  chapters  have  been  practically  rewritten,  and 
of  the  newer  operations,  all  those  of  special  value  have  been  described.  The 
number  of  illustrations  has  also  been  materially  increased.  Sixteen  valuable 
lithographic  plates  in  colors  and  sixty-one  text-figures  have  been  added,  thus 
greatly  enhancing  the  value  of  the  work.  There  is  no  doubt  that  the  volume 
in  its  new  edition  will  still  maintain  its  leading  position  as  a  substitute  for 
clinical  instruction. 


OPINIONS  OF  THE  MEDICAL  PRESS 


Philadelphia  MediceJ  Journal 

"  The  names  of  Zuckerkandl  and  DaCosta,  the  fact  that  the  book  has  been  translated 
into  13  different  languages,  together  with  the  knowledge  that  it  is  used  in  the  United  States 
Army  and  Navy,  would  be  sufficient  recommendation  for  most  of  us." 

Munchener  Medicinische  Wochenschrift 

"  We  know  of  no  other  work  that  combines  such  a  wealth  of  beautiful  illustrations  with 
clearness  and  conciseness  of  language,  that  is  so  entirely  abreast  of  the  latest  achievements, 
and  so  useful  both  for  the  beginner  and  for  one  who  wishes  to  increase  his  knowledge  of 
operative  surgerj'." 

Each  volume  is  edited,  with  additions,  by  a  leading  specialist 


SAUNDERS'    MEDICAL    HA  .YD- ATLASES 

Helferich  and  Bloodg'ood's 
Fractures  and  Dislocations 


Atlas  and  Epitome  of  Traumatic  Fractures  and  Dis= 
locations.  By  Professor  Dr.  H.  Helferich,  Professor  of 
Surgery  at  the  Royal  University,  Greifswald,  Prussia.  Edited, 
with  additions,  by  Joseph  C.  Bloodgood,  M.  D.,  Associate  in 
Surger}%  Johns  Hopkins  University,  Baltimore.  Ffo>?i  the  Fifth 
Revised  and  Enlarged  German  Edition.  With  216  colored 
illustrations  on  64  lithographic  plates,  190  text-cuts,  and  353 
pages  of  text.     Cloth,  $3.00  net. 

SHOWING  DEFORMITY.  X-RAY  SHADOW,  AND  TREATMENT 

This  department  of  medicine  being  one  in  which,  from  lack  of  practical 
knowledge,  much  harm  can  be  done,  and  in  which  in  recent  years  great 
importance  has  obtained,  a  book,  accurately  portraying  the  anatomic  rela- 
tions of  tlie  fractured  parts,  togetlier  with  the  diagnosis  and  treatment  of  the 
condition,  becomes  an  absolute  necessity.  This  present  work  fully  meets 
all  requirements.  As  complete  a  view  as  possible  of  each  case  has  been 
presented,  thus  equipping  the  physician  for  the  manifold  appearances  that 
he  will  meet  with  in  practice.  The  illustrations  show  the  visible  external 
deformity,  the  X-ray  shadow,  the  anatomic  preparation,  and  the  m'.-thod  of 
treatment. 


OPINIONS  OF  THE  MEDICAL  PRESS 


Medical  News,  New  York 

"  This  compact  and  exceedingly  attractive  little  volume  will  be  most  welcome  to  all 
who  are  interested  in  the  practical  application  of  anatomy.  The  author  and  editor  have 
made  a  most  successful  effort  to  arrange  the  illustrations  that  the  interpretation  of  what 
they  are  intended  to  present  is  exceedingly  easy." 

Brooklyn  Medical  Journal 

"  There  are  few  books  published  that  better  answer  the  requirements  for  illustration 
than  this  work  of  Professor  Helfcrirh.  .  .  .  Such  a  collection  of  illustrations  must  je  the 
result  of  much  labor  and  thought." 

They  are  Satisfactory  Substitutes  for  Clinical  Observation 


SAUNDERS'    MEDICAL   HAND-ATLASES 

Sultan  and  Coley's 
Abdominal  Hernias 


Atlas  and  Epitome  of  Abdominal  Hernias.  By  Privat- 
DOCENT  Dr.  Georg  Sultan,  of  Gottingen.  Edited,  with  addi- 
tions, by  William  B.  Coley,  M.  D.,  Clinical  Lecturer  on  Sur- 
gery, Columbia  University  (College  of  Physicians  and  Surgeons), 
New  York.  With  119  illustrations,  36  of  them  in  colors,  and 
277  pages  of  text.     Cloth,  $3.00  net. 

DEALING  WITH  THE  SURGICAL  ASPECT 

This  new  atlas  covers  one  of  the  most  important  subjects  in  the  entire 
domain  of  medical  teaching,  since  these  hernias  are  not  only  exceedingly 
common,  but  the  frequent  occurrence  of  strangulation  demands  extraordi- 
narily quick  and  energetic  surgical  intervention.  During  the  last  decade  the 
operative  side  of  this  subject  has  been  steadily  growing  in  importance,  until 
now  it  is  absolutely  essential  to  have  a  book  treating  of  its  surgical  aspect. 
This  present  atlas  does  this  to  an  admirable  degree.  The  illustrations  are 
not  only  very  numerous,  but  they  excel,  in  the  accuracy  of  the  portrayal  of 
the  conditions  represented,  those  of  any  other  work  upon  abdominal  hernias 
with  which  we  are  familiar.  The  work  will  be  found  a  worthy  exponent 
of  our  present  knowledge  of  the  subject  of  which  it  treats. 


PERSONAL  AND  PRESS  OPINIONS 


Robert  H.  M.  Dawbarn,  M.  D., 

Professor  of  Surgery  and  Surgical  Anatomy,  New  York  Polyclinic. 

"  I  have  spent  several  interested  hours  over  it  to-day,  and  shall  willingly  recommend 
it  to  my  classes  at  the  Polyclinic  College  and  elsewhere." 

Boston  Medical  and  Surgical  Journal 

"  For  the  general  practitioner  and  the  surgeon  it  will  be  a  very  useful  book  for  reference. 
The  book's  value  is  increased  by  the  editorial  notes  of  Dr.  Coley." 

They  have  already  appeeo-ed  in  thirteen  different  languages 


SAUXBERS'    MEDICAL    HAND-ATLASES  7 

Bruhl,  Politzer,  and 
MacCuen  Smith's  Otology 


Atlas  and  Epitome  of  Otology.  By  Gustav  Bruhl,  M.  D., 
of  Berlin,  with  the  collaboration  of  Professor  Dr.  A.  Politzer, 
of  Vienna.  Edited,  with  additions,  by  S.  JSIacCuen  Smith, 
M.  D.,  Professor  of  Otology  in  the  Jefferson  Medical  Col- 
lege, Philadelphia.  With  244  colored  figures  on  39  lithographic 
plates,  99  text-illustrations,  and  292  pages  of  text.  Cloth,  $3.00 
net. 

This  excellent  volume  is  the  first  attempt  to  supply  in  English  an  illus- 
trated clinical  handbook  to  act  as  a  worthy  substitute  for  personal  instruction 
in  a  specialized  clinic.  This  work  is  both  didactic  and  clinical  in  its  teach- 
ing, the   latter  aspect  being  especially  adapted  to  the   student's  wants. 

Clarence  J.  Blake,  M.  D., 

Professor  of  Otology,  Harvard  University  Medical  School,  Boston. 
"The  most  complete  work  of  its  kind  as  yet  published,  and  one  commending  itself  to 
both  the  student  and  teacher  in  the  character  and  scope  of  its  illustrations." 

Griinwald   and   Newcomb's 
Mouth,   Pharynx,   Nose 


Atlas  and  Epitome  of  Diseases  of  the  Mouth,  Pharynx, 

and  Nose.  By  Dr.  L.  Grunwald,  of  Munich.  Edited,  with 
additions,  by  James  E.  Newcomb,  M.  D.,  Instructor  in  Laryng- 
ology, Cornell  University  Medical  School.  With  200  illustra- 
tions on  42  colored  lithographic  plates,  41  text-cuts,  and  219 
pages  of  text.  Cloth,  $3.00  net. 
Journal  of  Ophthalmology,  Otology,  and    Laryngology 

"A  collection  of  the  most  naturally  colored  lithographic  plates  that  has  been  pub- 
lished in  any  book  in  the  English  language.  .  .  .  Very  valuable  alike  to  the  student,  the 
practitioner,  and  the  specialist." 


They  are  offered  at  a  price  heretofore  unapproached  in  cheapness 


SAUNDERS'   MEDICAL    HAND-ATLASES 

Sobotta  and  Huberts 
Human  Histology 


Atlas  and  Epitome  of  Human  Histology.    By  Pr.  Dr.  J. 

Sobotta,  of  Wiirzburg.  Edited,  with  additions,  by  G.  Carl 
HuBER,  M.  D.,  Professor  of  Histology  and  Embryology,  Univer- 
sity of  Michigan,  Ann  Arbor.  With  214  colored  figures  on  80 
plates,  68  text-cuts,  and  248  pages  of  text.     Cloth,  ^4.50  net. 

This  work  combines  an  abundance  of  well  chosen  and  most  accurate  illus- 
trations with  a  concise  text,  and  in  such  a  manner  as  to  make  it  both  atlas  and 
text-book.  The  colored  lithographic  plates  have  been  produced  with  the 
aid  of  over  thirty  colors,  and  particular  care  was  taken  to  avoid  distortion  and 
assure  exactness  of  magnification. 

Boston  Medical  and  Surgical  Journal 

"  In  color  and  proportion  they  are  characterized  by  gratifying-  accuracy  and  litho- 
graphic beauty.  .  .  .  May  be  highly  recommended  to  those  who  are  without  access  to  his- 
tologic collections." 

Haab   and    deSchweinitz's 
Operative  Ophthalmology 

Atlas  and  Epitome  of  Operative  Oplithalmology.     By 

Dr.  O.  Haab,  of  Ziirich.  Edited,  with  additions,  by  George 
E.  DE  ScHWEiNiTZ,  M.  D.,  Professor  of  Ophthalmology  in  the 
University  of  Pennsylvania.  With  30  colored  lithographic 
plates,  154  text-cuts,  and  377  pages  of  text.     Cloth,  $3.50  net. 

RECENTLY    ISSUED 

The  colored  illustrations  in  this  work  exhibit  the  same  perfection  of  art 
and  accurateness  of  detail  which   are  found  only  in  these  invaluable  atlases. 

Johns  Hopkins  Hospital  Bulletin 

"  The  descriptions  of  the  various  operations  are  so  clear  and  full  that  the  volume  can 
well  hold  place  with  more  pretentious  text-books." 

Unsurpassed  for  accuracy,  pictorial  beauty,  completeness,  cheapness 


SAUXDERS'    MEDICAL   HAND-ATLASES 


Haab  and  deSchweinitz's 
Ophthalmoscopy 

Atlas  and  Epitome  of  Ophthalmoscopy  and  Ophthal= 
moscopic  Diagnosis.  By  Dr.  O.  Haab,  of  Zurich.  From  the 
Third  Revised  and  Enlarged  German  Edition.  Edited,  with 
additions,  by  G.  E.  deSchweinitz,  M.  D.,  Professor  of  Oph- 
thahiwlogv,  University  of  Pennsylvania.  With  152  colored 
lithographic  illustrations;   85  pages  of  text.     Cloth,  $3.00  net. 

Not  only  is  the  student  made  acquainted  with  carefully  prepared  oph- 
thalmoscopic drawings  done  into  well-executed  lithographs  of  the  most 
important  fundus  changes,  but,  in  many  instances,  plates  of  the  microscopic 
lesions  are  added.     It  furnishes  a  manual  of  the  greatest  possible  service. 

The  Lancet,  London  .     ,.    w 

"  We  recommend  it  as  a  work  that  should  be  in  the  ophthalmic  wards  or  m  the  library 
of  every  hospital  into  which  ophthalmic  cases  are  received. 


Haab  and  deSchweinitz's 
External  Diseases  of  Eye 

Atlas  and  Epitome  of  External  Diseases  of  the  Eye. 

By  Dr.  O.  Haab,  of  Zurich.  Edited,  with  additions,  by  G.  E. 
deSchweinitz,  M.  D.,  Professor  of  Ophthalmology,  University 
of  Pennsylvania.  98  colored  illustrations  on  48  lithographic 
plates  and  232  pages  of  text.     Cloth,  $3.00  net. 

SECOND  REVISED  EDITION— RECENTLY  ISSUED 

In  this  thorough  revision  the  text  has  been  brought  up  to  date  by  the  addi- 
tion of  new  matter,  including  references  to  some  of  the  modern  therapeutic 
agents.     There  have  also  been  added  eight  chromolidiographic  plates. 

The  Medical  Record,  New  York 

"The  \v,.rk  is  excellently  suited  to  the  student  of  ophthalmologj'  and  to  the  practising 
sician.     It  cannot  fail  toattain  a  well-deserved  popularity."      i  Review  ot   previous  ed.) 


phys 


They  are  convenient  in  size  and  uniformly  bound 


SAUNDERS'  MEDICAL    HAND-ATLASES 


Diirck  and  Hektoen*s 
General  Pathologic  Histology 

Atlas  and   Epitome  of    General   Pathologic  Histology. 

By  Pr.  Dr.  H.  Durck,  of  Munich.  Edited,  with  additions,  by 
LuDviG  Hektoen,  M.  D.,  Professor  of  Pathology,  Rush  Medical 
College,  Chicago.  172  colored  figures  on  77  lithographic  plates, 
36  text-cuts,  many  in  colors,  and  453  pages  of  text.    $5.00  net. 

JUST    ISSUED 

Many  of   the    magnificent  illustrations    required    twenty-six  colors  to  re- 
produce them. 

W.  T.  Councilman,  M.D., 

Professor  of  Pathologic  Anatotity,  Harvard  University. 

"I  have  seen  no  plates  which  impress  me  as  so  trulj' representing  histolog-ic  appear- 
ances as  do  these.  °  s,         vv  <^^ 


Diirck  and  Hektoen's 
Special  Pathologic  Histology 

Atlas  and    Epitome  of    Special    Pathologic    Histology. 

By  Dr.  H.  Durck,  of  Munich.  Edited,  with  additions,  by 
LuDviG  Hektoen,  M.  D.,  Professor  of  Pathology,  Rush  Medical 
College,  Chicago.  In  Two  Parts.  Part  I. — Circulatory,  Respira- 
tory, and  Gastrointestinal  Tracts.  Part  II.— Liver,  Urinary  and 
Sexual  Organs,  Nervous  System,  Skin,  Muscles,  and  Bones.  243 
colored  figures  on  122  plates,  and  350  pages  of  text.  Per  part: 
Cloth,  ^3,00  net. 

William  H.  Welch,  M.  D., 

Professor  of  Pathology ,  Jolms  Hopkins  University,  Balti7nore. 

"  I  consider  Diirck's  'Atlas  of  Special  Pathologic  Histology,'  edited  by  Hektoen   a  ver\' 
useful  book  for  students  and  others.     The  plates  are  admirable."  ' 


They  represent  the  best  artistic  and  professional  talent 


SAUNDERS'    MEDICAL   HAND-ATLASES 


Lehmann,  Neumann,  and 
Weaver's  Bacteriology 


Atlas  and  Epitome  of  Bacteriology :  including  a  Text- 
Book  OF  Special  Bacteriologic  Diagnosis.  By  Prof.  Dr. 
K.  B.  Lehmann  and  Dr.  R.  O.  Neumann,  of  Wiirzburg.  Frojn 
the  Second  Revised  and  Enlarged  Gennan  Edition.  Edited, 
with  additions,  by  G.  H.  Weaver,  M.  D.,  Assistant  Professor 
of  Pathology  and  Bacteriology,  Rush  Medical  College,  Chicago. 
In  two  parts.  Part  I.— 632  colored  figures  on  69  lithographic 
plates.  Part  II.— 511  pages  of  text,  illustrated.  Per  part: 
Cloth,  $2.50  net. 

INCLUDING  SPECIAL  BACTERIOLOGIC  DIAGNOSIS 

This  work  furnishes  a  survey  of  the  properties  of  bacteria,  together  with 
the  causes  of  disease,  disposition,  and  immunity,  reference  being  constantly 
made  to  an  appendix  of  bacteriologic  technic.  The  special  part  gives  a 
complete  description  of  the  important  varieties,  the  less  important  ones  being 
mentioned  when  worthy  of  notice.  The  lithographic  plates,  as  in  all  this 
series,  are  accurate  representations  of  the  conditions  as  actually  seen,  and 
this  collection,  if  anything,  is  more  handsome  than  any  of  its  predecessors. 
As  an  aid  in  original  investigation  the  work  is  invaluable. 


OPINIONS  OF  THE  MEDICAL  PRESS 


American  Journal  of  the  Medical  Sciences 

"Practically  all  the  important  organisms  are  represented,  and  in  such  a  variety  of 
forms  and  cultures  that  any  other  atlas  would  rarely  be  needed  in  the  ordinary  hospita. 
laboratory." 

The  Lancet.  London 

"  We  have  found  the  work  a  more  trustworthy  guide  for  the  recognition  of  unfamiliai 
species  than  any  with  which  we  are  acquainted."  ^^ 

There  have  been  82,000  copies  imported  since  publication 


12  SAUNDERS'    MEDICAL   HAND-ATLASES 

Schaffer  and  Edgar's 
Labor  an^  Operative  Obstetrics 

Atlas  and  Epitome  of  Labor  and  Operative  Obstetrics. 

By  Dr.  O.  Schaffer,  of  Heidelberg.  From  the  Fifth  Revised 
and  Enlai-ged  German  Edition.  Edited,  with  additions,  by 
J.  Clifton  Edgar,  M.  D.,  Professor  of  Obstetrics  and  Clinical 
Midwifery,  Cornell  University  Medical  School.  14  lithographic 
plates  in  colors;   139  other  cuts;   in  pages  of  text.     ^2.00  net. 

The  book  presents  the  act  of  parturition  and  the  various  obstetric  opera- 
tions in  a  series  of  easily  understood  illustrations.  These  are  accompanied 
by  a  text  that  treats  the  subject  from  a  practical  standpoint. 

Dublin  Journal  of  Medical  Science,  Dublin 

'■  One  fault  Professor  Schaffer's  Atlases  possess.  Their  name,  and  the  extent  and 
number  of  the  illustrations,  are  apt  to  lead  one  to  suppose  that  they  are  merely  '  atlases,' 
whereas  the  truth  really  is  they  are  also  concise  and  modern  epitomes  of  obstetrics." 


Schaffer  6  Edgar's  Obstetric 
Diagnosis  and  Treatment 


Atlas  and  Epitome  of  Obstetric  Diagnosis  and  Treat= 
ment.  By  Dr.  O.  Schaffer,  of  Heidelberg.  From  the  Sec- 
ond Revised  German  Edition.  Edited,  with  additions,  by  J. 
Clifton  Edgar,  M.  D.,  Professor  of  Obstetrics  and  Clinical 
Midwifer}^,  Cornell  University  Medical  School.  122  colored  fig- 
ures on  56  plates;   38  other  cuts;  315  pages  of  text.     $3.00  net. 

Tliis  book  treats  particularly  of  obstetric  operations,  and,  besides  the 
wealth  of  beautiful  lithographic  illustrations,  contains  an  extensive  text  of 
great  value.      This  text  deals  with  the  practical,  clinical  side  of  the  subject. 

New  York  Medical  Journal 

"  The  illustrations  are  admirably  executed,  as  they  are  in  all  of  these  atlases,  and  the 
text  can  safely  be  commended,  not  only  as  elucidatory  of  the  plates,  but  as  expounding  the 
scientific  midwifery  of  to-day." 

These  are  the  famous  "  Lehmeoin  medicinische  Handatlemten  " 


SAiW'DEJRS'    MEDICAL    HAND-ATLASES  13 

Mracek   and  Stelwag'on*s 
Skin 

Atlas  and  Epitome  of  Diseases  of  the  Skin.  By  Prof. 
Dr.  Franz  Mracek,  of  Vienna.  Edited,  with  additions,  by 
Henry  W.  Stelwagon,  M.  D.,  Professor  of  Dermatology  in 
the  Jefferson  Medical  College,  Philadelphia.  With  77  colored 
plates,  50  text-cuts,  and  288  pages  of  text.      Cloth,  ^4.00  net. 

JUST  ISSUED— NEW  (2dj  EDITION 

This  volume,  the  outcome  of  years  of  scientific  and  artistic  work,  con- 
tains, together  with  colored  plates  of  unusual  beauty,  numerous  illustrations 
in  black,  and  a  text  comprehending  the  entire  field  of  dermatology.  The 
illustrations  are  all  original  and  prepared  from  actual  cases  in  Mracek's  clinic. 

American  Journal  of  the  Medical  Sciences 

"  The  advantages  which  we  see  in  this  book  and  which  recommend  it  to  our  minds  are : 
First,  its  handiness;  secondly,  the  plates,  which  are  excellent  as  regards  drawing,  color, 
and  the  diagnostic  points  which  they  bring  out.      We  most  heartily  recommend  it." 

Mracek  and  Bang's 
Syphilis  and  Venereal  Diseases 

Atlas  and  Epitome  of  Syphilis  and  the  Venereal  Dis= 
eases.  By  Prof.  Dr.  Franz  Mr.acek,  of  Vienna.  Edited,  with 
additions,  by  L.  Bolton  Bangs,  M.  D.,  late  Prof,  of  Genito- 
urinary Surgery,  University  and  Bellevue  Hospital  Medical 
College,  New  York.  With  71  colored  plates  and  122  pages 
of  text.     Cloth,  $3.50  net. 

According  to  the  unanimous  opinion  of  numerous  authorities,  to  whom 
the  original  illustrations  of  this  book  were  presented,  they  surpass  in  beauty 
anything  of  the  kind  that  has  been  produced  in  this  field,  not  only  in  Ger- 
many, but  throughout  the  literature  of  the  world. 

Robert  L.  Dickinson,  M.  D.. 

Art  Editor  of  "  The  American  Text-Book  of  Obstetrics." 

"The  book  that  appeals  instantly  to  me  for  the  strikingly  successful,  valuable,  and 

faphic  character  of  its  ilkisiraiions  is  the  '  .Atlas  of  Syphilis  and  the  Venereal   Diseases.' 
know  of  nothing  in  this  country  that  can  compare  with  it." 

The  lithographs,  all  made  in  Germzmy,  are  unrivalled 


14  SAUNDERS'  MEDICAL    HAND-ATLASES 

Schaffer  and  Webster's 
Operative  Gynecology 

Atlas  and  Epitome  of  Operative  Gynecology.     By  Dr. 

O.  Schaffer,  of  Heidelberg.  Edited,  with  additions,  by  J. 
Clarence  Webster,  M.  D.  (Edin.),  F.  R.  C.  P.  E.,  Professor  of 
Obstetrics  and  Gynecology  in  the  Rush  Medical  College,  in  affili- 
ation with  the  University  of  Chicago.  With  42  lithographic 
plates  in  colors,  many  text-cuts,  a  number  in  colors,  and  138 
pages  of  text.     Cloth,  $3.00  net. 

RECENTLY  ISSUED 

The  excellence  of  the  lithographic  plates  and  the  many  other  illustrations 
in  this  atlas  render  it  of  the  greatest  value  in  obtaining  a  sound  and  practical 
knowledge  of  operative  gynecology.  They  are  based  on  hundreds  of  photo- 
graphs taken  from  nature,  and  faithfully  reproduced. 

Medical  Record,  New  York 

'■  The  Tolume  should  prove  most  helpful  to  students  and  others  in  grasping  details 
usually  to  be  acquired  only  in  the  amphitheatre  itself." 

Shaffer  and   Norris* 
Gynecology 

Atlas  and  Epitome  of  Gynecology.  By  Dr.  O.  Shaffer, 
of  Heidelberg.  From  the  Second  Revised  and  Enlarged  German 
Edition.  Edited,  with  additions,  by  Richard  C.  Norris,  A.  M., 
M.  D.,  Gynecologist  to  Methodist-Episcopal  and  Philadelphia 
Hospitals.  With  207  colored  figures  on  90  plates,  65  text-cuts, 
and  308  pages  of  text.     Cloth,  $3.50  net. 

The  value  of  this  atlas  will  be  found  not  only  in  the  concise  explanatory 
text,  but  especially  in  the  illustrations.  The  large  number  of  colored  plates, 
reproducing  the  appearance  of  fresh  specimens,  will  give  the  student  a  knowl- 
edge of  the  changes  induced  by  disease  that  cannot  be  obtained  from  mere 
description. 

Bulletin  of  Johns  Hopkins  Hospital,  Baltimore 

"  The  book  contains  much  valuable  material.  Rarely  have  we  seen  such  a  valuable 
collection  of  gynecological  plates." 

These  books  are  next  best  to  actual  clinical  work 


SAUNDERS'    MEDICAL   HAND-ATLASES  15 

Jakob  and  Eshner's 
Internal  Medicine  &  Diag'nosis 

Atlas  and  Epitome  of  Internal  Medicine  and  Clinical 
Diagnosis.  By  Dr.  Chr.  Jakob,  of  Erlangen.  Edited,  with 
additions,  by  Augustus  A.  Eshner,  M.  D.,  Professor  of  Clin- 
ical Medicine  in  the  Philadelphia  Polyclinic.  With  182  colored 
figures  on  68  plates,  64  illustrations  in  black  and  white,  and 
259  pages  of  text.     Cloth,  $3.00  net. 

In  addition  to  an  admirable  atlas  of  clinical  microscopy,  this  volume 
describes  the  physical  signs  of  all  internal  diseases  in  an  instructive  manner 
by  means  of  fifty  colored  schematic  diagrams.  As  a  means  of  instruction 
its  value  is  very  great ;  as  a  reference  handbook  it  is  admirable. 

British  Medical  Journal 

"  Dr.  Jakob's  work  deserves  nothing  but  praise.  The  information  is  accurate  and  up 
to  present-day  requirements." 

Grunwald  and  Grayson's 
Diseases  of  the  Larynx 

Atlas  and  Epitome  of  Diseases  of  the  Larynx.     By  Dr. 

L.  Grunwald,  of  Munich.  Edited,  with  additions,  by  Charles 
P.  Grayson,  M.  D.,  Clinical  Professor  of  Laryngology  and 
Rhinology,  University  of  Pennsylvania.  With  107  colored 
figures  on  44  plates,  25  text-illustrations,  and  103  pages  of  text. 
Cloth,  $2.50  net. 

This  atlas  exemplifies  a  happy  blending  of  the  didactic  and  clinical,  such 
as  is  not  to  be  found  in  any  other  volume  upon  this  subject.  The  author 
has  given  special  attention  to  the  clinical  portion  of  the  work,  the  sections 
on  diagnosis  and  treatment  being  particularly  full. 

The  Medical  Record,  New  York 

"  This  is  a  good  work  of  reference,  being  both  practical  and  concise.  ...  It  is  a  valu- 
able addition  to  existing  laryngeal  text-bouks." 

For  "  Special  Offer  "  regarding  these  atlases  see  page  I 


i6  SAUNDERS'  MEDICAL   HAND-."  TLASES 

Hofmann  and  Peterson's 
Leg'al  Medicine 

Atlas  of  Legal  Medicine.  By  Dr.  E.  von  Hofmann,  of 
Vienna.  Edited  by  Frederick  Peterson,  M.  D.,  Clinical  Pro- 
fessor of  Psychiatry,  College  of  Physicians  and  Surgeons,  N.  Y. 
1 20  colored  figures  on  56  plates,  193  text-cuts.  ^3.50  net. 
The  Practitioner,  London 

"  The  illustrations  appear  to  be  the  best  that  have  ever  been  published  in  connection 
with  this  department  of  medicine,  and  they  cannot  fail  to  be  useful  alike  to  the  medical 
jurist  and  to  the  student  of  forensic  medicine." 

Jakob  and  Fisher's 
Nervous  System  and  its  Diseases 

Atlas  and  Epitome  of  the  Nervous  System  and  its 
Diseases.  By  Prof.  Dr.  Chr.  Jakob,  of  Erlangen.  From  the 
Second  Revised  German  Edition.  Edited,  with  additions,  by 
Edward  D.  Fisher,  M.  D.,  Professor  of  Diseases  of  the  Nervous 
System,  University  and  Bellevue  Hospital  Medical  College,  N.  Y. 
83  plates  and  copious  text.  Cloth,  $3.50  net. 
Philadelphia  Medical  Journal 

"We  know  of  no  one  work  of  anything  like  equal  size  which  covers  this  important  and 
complicated  field  with  the  clearness  and  scientific  fidelity  of  this  hand-atlas." 

Golebiewski  and  Bailey's 
Accident  Diseases 

Atlas  and  Epitome  of  Diseases  Caused  by  Accidents. 

By  Dr.  Ed.  Golebiewski,  of  Berlin.  Edited,  with  additions, 
by  Pearce  Bailey,  M.  D.,  Consulting  Neurologist  to  St.  Luke's 
Hospital  and  Orthopedic  Hospital,  N.  Y.  71  colored  illustrations 
on  40  plates,  143  text-cuts,  549  pages  of  text.  Cloth,  $4.00  net. 
Medical  Examiner  and  Practitioner 

"  It  is  a  useful  addition  to  life-insurance  libraries,  for  lawyers,  physicians,  and  for  every 
one  who  is  brought  in  contact  with  the  treatment  or  consideration  of  accidents  or  diseases 
growing'  out  of  them,  or  legal  complications  flowing  from  them." 

The  "Atlas  of  Operative  Surgery"  has  been  adopted  by  U.  S.  Army 


COLUMBIA  UNIVERSITY  LIBRARIES  (hsl.stx) 

RK  51  P922  C.2 

Atlas  and  text-book  of  dentistrv 


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